concanavalin-a and Autoimmune-Diseases

Unbalanced Th1/Th2 T-cell responses in the liver are a characteristic of hepatic inflammation and subsequent liver fibrosis. The recently discovered Th17 cells, a subtype of CD4(+) T-helper cells mainly producing IL-17 and IL-22, have initially been linked to host defense against infections and to autoimmunity. Their preferred differentiation upon TGFβ and IL-6, two cytokines abundantly present in injured liver, makes a contribution of Th17 cells to hepatic inflammation very likely. Indeed, initial studies in humans revealed activated Th17 cells and Th17-related cytokines in various liver diseases. However, functional experiments in mouse models are not fully conclusive at present, and the pathogenic contribution of Th17 cells to liver inflammation might vary upon the disease etiology, for example, between infectious and autoimmune disorders. Understanding the chemokines and chemokine receptors promoting hepatic Th17 cell recruitment (possibly CCR6 or CCR4) might reveal new therapeutic targets interfering with Th17 migration or differentiation in liver disease.

Topics: Animals; Autoimmune Diseases; Autoimmunity; Cell Differentiation; Cell Movement; Chemical and Drug Induced Liver Injury; Concanavalin A; Disease Models, Animal; Humans; Infections; Inflammation; Interleukin-17; Interleukin-22; Interleukins; Liver; Liver Diseases; Mice; Receptors, Chemokine; T-Lymphocytes, Regulatory; Th17 Cells; Transforming Growth Factor beta

Phytohemagglutinin was prominent in the evaluation of the immunosuppressive effects of mitogenic lectins that started in 1965 and continued for two decades. Basic studies elucidated the inhibitory actions of PHA on humoral and cellular immune responses in mice, rats, and guinea pigs. Some suppressive effects of this and other mitogens including lentil lectin and Con A were demonstrated on renal, skin, pancreas, and heart allograft rejections in mice, rats, and dogs. In addition to their inherent suppressive activities, these substances have been shown to potently augment the suppression generated by conventional agents. More relevant to tolerance-inducing modulations, the Rigas group showed that in vitro incubation of the parental spleen cells with PHA in the F1 hybrid model before giving them to the F1 mouse virtually abolished the GvH responses. Their explanation was that the donor cells were rendered unresponsive by their reversion to an immature state in which they lost the essential surface receptors. Similar spleen cell suppression was generated by systemic administration of PHA to the parental donor prior to their administration. A method is proposed here for establishing tolerance to either newly introduced or firmly established antigens applying the L4 isolectin of PHA to make non-reactive all T lymphocytes that remain functional in conjunction with full suppression by conventional agents. During the vulnerable period of drug-induced suppression, the host would be protected from infection and bleeding by full nonspecific proliferative activation of the lymphoid and myeloid systems. The establishment of allograft tolerance by preemptive inhibition of responses to newly introduced transplant antigens would be easier to achieve than the reversal of firmly established responses to antigens involved in GvH reactions and autoimmune diseases. The studies of von Boehmer and Kisielow in a transgenic mouse model confirmed that clonal deletion does occur in the thymus whereby corresponding specific thymocytes are destroyed when they encounter self-antigens. Their work suggested that tolerance to self-antigens might be established if immune responses against putative antigen peptides were blocked sufficiently that they would be released to reach the central or peripheral residence sites of their immunologically reactive clones for deletion to occur. This approach to suppressive therapy would be useful for managing the problems of allograft rejection, GvH rea

Topics: Animals; Autoimmune Diseases; Concanavalin A; Dogs; Graft Rejection; Graft vs Host Disease; Humans; Immunosuppressive Agents; Lectins; Mice; Phytohemagglutinins; Rats; Transplantation Immunology

Topics: Animals; Autoimmune Diseases; Chemical and Drug Induced Liver Injury; Concanavalin A; Disease Models, Animal; Galactosamine; Humans; Infections; Lipopolysaccharides; Liver Diseases; Tumor Necrosis Factor-alpha

Autoimmune chronic active hepatitis is a disease of unknown aetiology in which a dense mononuclear cell infiltrate in the portal areas of the liver is associated with ongoing necrosis of periportal hepatocytes. The finding of autoantibodies in serum, an increased frequently of HLA B8 DR3, a female predominance, an association with autoimmune diseases and the histological features all suggest a role for immunological reactions in the pathogenesis. Various immunological reactions have been demonstrated in vitro which could be of relevance to pathogenesis, including antibodies in serum directed against antigens expressed on the liver cell membrane, antibody-dependent cell-mediated cytotoxicity for autologous hepatocytes. T cell sensitisation to undefined hepatocyte antigen(s) and both antigen- and non-antigen-specific suppressor T cell defects. However, it is still unclear how these various phenomena interact in vivo and further studies are required to clarify their exact role in pathogenesis.

Topics: Antibody-Dependent Cell Cytotoxicity; Autoantibodies; Autoimmune Diseases; Cell Membrane; Concanavalin A; Female; Hepatitis, Chronic; Histocompatibility Antigens Class II; HLA Antigens; HLA-B8 Antigen; HLA-DR3 Antigen; Humans; Immunity, Cellular; Liver; Male; T-Lymphocytes, Regulatory

We have compared the in vitro and in vivo mitogenic and polyclonal antibody (IgM-, IgG-, IgA- and IgM anti-SRBC-secreting PFC) and autoantibody (IgM anti-ssDNA-, anti-bromelin-treated [HB]- and anti-intact mouse RBC-secreting PFC) responses to peptidoglycan (PG), LPS, protein A, PWM, PHA and Con A in young (4-7 weeks) and old (7-8 months) normal (BALB/c, CBA/H, C57BL/6) and autoimmune (NZB, NZB X NZW F1, BXSB, MRL/1; old BXSB and MRL/1 were 4-5 months) mice. Our results demonstrated that: lymphocytes from young and old autoimmune mice (except old BXSB) could be further polyclonally activated in vitro by PG or LPS as well as or better than lymphocytes from young and old normal mice; lymphocytes from young or old autoimmune mice were less polyclonally activated in vitro by protein A or PWM, respectively, than lymphocytes from young or old normal mice; PG and LPS were equally effective polyclonal activators in vitro; in vivo, LPS was a stronger stimulant than PG; in vivo, LPS could induce polyclonal activation in both young and old normal and autoimmune mice, whereas, PG could only induce polyclonal activation in vivo in young and old normal mice, but did not induce further activation in young and old autoimmune mice; only some tests (anti-ssDNA and IgG PFC in vivo, and IgA and anti-HB MRBC PFC in vitro) revealed higher responses in autoimmune than in normal mice, and these higher responses were seen more often in vivo than in vitro; both autoimmune and normal mice had a high frequency of autoantibody (especially anti-ssDNA) secreting cells in polyclonal activation in vitro, whereas a high frequency of these cells in vivo was only found in autoimmune mice; in most cases in vitro, polyclonal activators did not change the frequency of autoantibody and heteroantibody secreting cells, but in vivo, both PG and LPS increased the frequency of anti-ssDNA antibody secreting cells in normal, but not in autoimmune, mice; LPS increased the in vivo, but not in vitro, frequency of cells secreting anti-HB MRBC antibodies in some strains of mice; old mice had lower mitogenic responsiveness than young mice in both autoimmune and normal strains; autoimmune mice had similar, higher or lower mitogenic responses than normal mice, depending on the strain and the age, but in most cases consistent for both B and T cell mitogens; and there was no correlation between the patterns of increased or decreased mitogenic and polyclonal antibody responses in normal and autoimmune mice.4+.

Topics: Age Factors; Animals; Antibody Formation; Autoantibodies; Autoimmune Diseases; Concanavalin A; Female; In Vitro Techniques; Lipopolysaccharides; Lymphocyte Activation; Mice; Mice, Inbred Strains; Peptidoglycan; Phytohemagglutinins; Pokeweed Mitogens; Staphylococcal Protein A

Topics: Adult; Antigen-Antibody Complex; Autoantibodies; Autoimmune Diseases; Child; Concanavalin A; Graves Disease; Humans; T-Lymphocytes, Regulatory; Thyroglobulin; Thyroid Gland; Thyroid Neoplasms

Topics: Agammaglobulinemia; alpha-Fetoproteins; Antibodies; Antibody Formation; Autoimmune Diseases; B-Lymphocytes; Concanavalin A; DNA; Epitopes; Genes, MHC Class II; Growth Inhibitors; Hybrid Cells; Hypersensitivity; Immune Tolerance; Immunity, Cellular; Immunoglobulins; Immunotherapy; Interferons; Lymphocyte Culture Test, Mixed; Multiple Myeloma; Nucleotides, Cyclic; Prostaglandins; T-Lymphocytes; T-Lymphocytes, Regulatory; Terminology as Topic; Thymus Hormones

Topics: Animals; Antibodies, Antinuclear; Antigen-Antibody Complex; Autoantibodies; Autoimmune Diseases; B-Lymphocytes; Concanavalin A; Cytotoxicity, Immunologic; HLA Antigens; Humans; Lupus Erythematosus, Systemic; Lymphocyte Activation; T-Lymphocytes

Topics: Agammaglobulinemia; Animals; Antigens; Autoimmune Diseases; Binding, Competitive; Cell Transformation, Neoplastic; Chickens; Concanavalin A; Dysgammaglobulinemia; Epitopes; Genes; Humans; Immune Tolerance; Immunity, Cellular; Immunoglobulin A; Immunoglobulin Allotypes; Immunoglobulin E; Immunologic Deficiency Syndromes; Immunosuppression Therapy; Lymphokines; Mice; Mycoses; Rabbits; T-Lymphocytes

Topics: Agammaglobulinemia; Animals; Antibody Formation; Antibody Specificity; Antigens; Antilymphocyte Serum; Autoimmune Diseases; Binding, Competitive; Cell Separation; Concanavalin A; Epitopes; Hemolytic Plaque Technique; Hypersensitivity, Delayed; Immunity, Cellular; Immunologic Memory; Immunosuppression Therapy; Lymphocyte Culture Test, Mixed; Lymphokines; Mice; Spleen; T-Lymphocytes; Thymectomy

Autoimmune hepatitis represents a ubiquitous human health problem and has a poor prognosis. Dihydroquercetin (DHQ), a well-known antioxidant, significantly inhibits fulminant hepatitis through anti-oxidant and anti-inflammation mechanisms. In this study, we show that administration of DHQ ameliorated concanavalin A (ConA)-induced mouse liver injury by increasing the survival rate, reducing the serum ALT and AST level, preventing histopathological injuries and decreasing pro-inflammatory cytokine mRNA expression in hepatic tissue. As macrophages/Kupffer cells in oxidative stress and pro-inflammatory mediators play an important role in the pathogenesis of immune-mediated hepatitis, we further exposed mouse RAW264 macrophage cell lines to ConA in vitro and found that DHQ significantly inhibited mRNA expression and secretion of IFN-γ and TNF-α in cell culture supernatant. In addition, DHQ significantly enhanced heme oxygenase-1 (HO-1) expression in a dose- and time-dependent manner via increased Nrf2 expression in cytoplasm and nuclear translocation. Furthermore, DHQ enhanced phosphorylation of three members of the mitogen-activated protein kinase (MAPK) family, and cell treatment with MEK/ERK (PD98059), p38 (SB203580) and JNK (SP600125) inhibitors reduced DHQ-induced HO-1 expression. These results indicate that DHQ possesses hepatoprotective properties against ConA-induced liver injury, which are attributed to its ability to scavenge oxidative stress and to inhibit the release of inflammatory mediators via upregulation of HO-1 activity through the MAPK/Nrf2 signaling pathway in macrophages/Kupffer cells.

Topics: Animals; Antioxidants; Autoimmune Diseases; Cell Line; Concanavalin A; Extracellular Signal-Regulated MAP Kinases; Heme Oxygenase-1; Hepatitis; Humans; Immunity; Interferon-gamma; Macrophages; Male; Membrane Proteins; Mice; Mice, Inbred C57BL; Models, Animal; NF-E2-Related Factor 2; Quercetin; Signal Transduction; Tumor Necrosis Factor-alpha

Severe liver injury that occurs when immune cells mistakenly attack an individual's own liver cells leads to autoimmune hepatitis. In mice, acute hepatitis can be induced by concanavalin A (ConA) treatment, which causes rapid activation of CD1d-positive natural killer (NK) T cells. These activated NKT cells produce large amounts of cytokines, which induce strong inflammation that damages liver tissues. Here we show that PKC-θ(-/-) mice were resistant to ConA-induced hepatitis due to essential function of PKC-θ in NKT cell development and activation. A dosage of ConA (25 mg/kg) that was lethal to wild-type (WT) mice failed to induce death resulting from liver injury in PKC-θ(-/-) mice. Correspondingly, ConA-induced production of cytokines such as IFNγ, IL-6, and TNFα, which mediate the inflammation responsible for liver injury, were significantly lower in PKC-θ(-/-) mice. Peripheral NKT cells had developmental defects at early stages in the thymus in PKC-θ(-/-) mice, and as a result their frequency and number were greatly reduced. Furthermore, PKC-θ(-/-) bone marrow adoptively transferred to WT mice displayed similar defects in NKT cell development, suggesting an intrinsic requirement for PKC-θ in NKT cell development. In addition, upon stimulation with NKT cell-specific lipid ligand, peripheral PKC-θ(-/-) NKT cells produced lower levels of inflammatory cytokines than that of WT NKT cells, suggesting that activation of NKT cells also requires PKC-θ. Our results suggest PKC-θ is an essential molecule required for activation of NKT cell to induce hepatitis, and thus, is a potential drug target for prevention of autoimmune hepatitis.

Topics: Animals; Autoimmune Diseases; Concanavalin A; Hepatitis, Animal; Inflammation; Isoenzymes; Lymphocyte Activation; Mice; Mice, Knockout; Natural Killer T-Cells; Protein Kinase C; Protein Kinase C-theta

Con A-induced hepatitis has been used as a model of human autoimmune or viral hepatitis. During the process of identifying immunologically bioactive proteins in human plasma, we found that apolipoprotein A-II (ApoA-II), the second major apolipoprotein of high-density lipoprotein, inhibited the production of IFN-γ by Con A-stimulated mouse and human CD4 T cells. Con A-induced hepatitis was attenuated by the administration of ApoA-II. The beneficial effect of ApoA-II was associated with reduced leukocyte infiltration and decreased production of T cell-related cytokines and chemokines in the liver. ApoA-II inhibited the Con A-induced activation of ERK-MAPK and nuclear translocation of NFAT in CD4 T cells. Interestingly, exacerbated hepatitis was observed in ApoA-II-deficient mice, indicating that ApoA-II plays a suppressive role in Con A-induced hepatitis under physiological conditions. Moreover, the administration of ApoA-II after the onset of Con A-induced hepatitis was sufficient to suppress disease. Thus, the therapeutic effect of ApoA-II could be useful for patients with CD4 T cell-related autoimmune and viral hepatitis.

Topics: Animals; Apolipoprotein A-II; Autoimmune Diseases; CD4-Positive T-Lymphocytes; Cell Migration Inhibition; Cell Movement; Concanavalin A; Female; Gene Knockout Techniques; Growth Inhibitors; Hepatitis, Animal; Humans; Interferon-gamma; Mice; Mice, Inbred BALB C; Mice, Knockout

Interleukin-17 (IL-17)-producing cells are increasingly considered to be the major pathogenic population in various autoimmune disorders. The effects of glucocorticoids, widely used as therapeutics for inflammatory and autoimmune disorders, on IL-17 generation have not been thoroughly investigated so far. Therefore, we have explored the influence of methylprednisolone (MP) on IL-17 expression in rat lymphocytes, and compared it to the effect of the drug on interferon (IFN)-gamma.. Production of IL-17 in mitogen-stimulated lymph node cells (LNC) from non-treated rats, as well as in myelin basic protein (MBP)-stimulated draining LNC from rats immunized with spinal cord homogenate and complete Freund's adjuvant was significantly reduced by MP. The reduction was dose-dependent, sustained through the follow-up period of 48 hours, and was not achieved through anti-proliferative effect. Additionally, MP inhibited IL-17 production in purified T cells as well, but to less extent than in LNC. In its influence on IL-17 production MP inhibited Ror-gammaT transcription factor expression, as well as Jun phosphorylation, but not ERK or p38 activation in mitogen-stimulated LNC. Importantly, MP collaborated with IFN-gamma in inhibiting IL-17 generation in LNC.. The observed difference in the effect of MP on IL-17 and IFN-gamma could be important for the understanding of the variability in the efficiency of glucocorticoids in the treatment of autoimmune diseases.

Topics: Animals; Autoimmune Diseases; Concanavalin A; Dose-Response Relationship, Immunologic; Guinea Pigs; Immunization; Interferon-gamma; Interleukin-17; Lymphocyte Activation; MAP Kinase Signaling System; Methylprednisolone; Myelin Basic Protein; Rats; Spinal Cord; T-Lymphocytes; Tissue Extracts

Concanavalin A-induced hepatotoxicity was compared in lipodystrophic aP2-nSREBP-1c transgenic mice (LD mice) lacking adipose tissue, obese leptin-deficient ob/ob mice, and lean wild-type (WT) mice. Serum leptin and adiponectin were low in LD mice, whereas ob/ob mice had undetectable leptin, but high adiponectin. Protection from hepatotoxicity was observed in ob/ob, but not in LD mice, despite low cytokine levels and reduced T cell activation and hepatic natural killer T cells in both groups. Administration of adiponectin protected LD mice from hepatotoxicity without altering cytokine levels. In contrast, administration of leptin heightened disease susceptibility by restoring cytokine production. Neutralization of TNF alpha protected LD mice from liver damage. Increased in vivo susceptibility to the hepatotoxic effect of TNF alpha was observed in LD mice. In vitro, adiponectin protected primary hepatocytes from TNF alpha-induced death, whereas leptin had no protective effect. In conclusion, although leptin increases susceptibility to hepatotoxicity by regulating cytokine production and T cell activation, adiponectin protects hepatocytes from TNF alpha-induced death.

Topics: Adiponectin; Animals; Apoptosis; Autoimmune Diseases; CCAAT-Enhancer-Binding Proteins; Concanavalin A; Cytokines; DNA-Binding Proteins; Hepatitis; In Situ Nick-End Labeling; Intercellular Signaling Peptides and Proteins; Killer Cells, Natural; Leptin; Lipodystrophy; Lymphocyte Activation; Mice; Mice, Obese; Mice, Transgenic; Obesity; Sterol Regulatory Element Binding Protein 1; T-Lymphocytes; Transcription Factors; Tumor Necrosis Factor-alpha

To investigate whether activity and glucocorticoid treatment of rheumatic diseases are reflected by selected parameters of cellular energy metabolism of peripheral blood mononuclear cells (PBMC).. PBMC were obtained from 30 healthy volunteers, 28 patients (16 inactive; 12 active) with rheumatoid arthritis, systemic lupus erythematosus, vasculitis, or other autoimmune diseases, and five patients with infectious diseases. Patients with active rheumatic diseases were examined before and 4-5 days after starting, restarting, or increasing the dose of glucocorticoids. Cellular oxygen consumption (as a measure of ATP production), bioenergetic ability to be stimulated, and major ATP consuming processes were measured amperometrically with a Clark electrode.. A normal value for oxygen consumption of 3.84 (SEM 0.1) (all data in nmol O(2)/min/10(7) cells) independent of sex was found. In patients with inactive disease the respiration rate was slightly higher, but was significantly increased in active patients to 4.82 (SEM 0.33) (p<0.001). PBMC from active patients showed a significantly lower bioenergetic response to a mitogenic stimulus than controls (p<0.05). In stimulated cells from active patients there was a significant reduction in cation transport and protein synthesis. All parameters above were almost normalised within 4-5 days upon optimised treatment with glucocorticoids. For comparison, PBMC from patients with active infectious diseases also showed an increased respiration rate; their response to mitogenic stimulation was even higher.. This study shows for the first time that parameters describing the cellular function of PBMC in bioenergetic terms are suitable for (a) describing semiquantitatively the activity of a rheumatic disease and (b) assessing the therapeutic effect on the disease.

Topics: Adolescent; Adult; Aged; Antirheumatic Agents; Autoimmune Diseases; Cell Culture Techniques; Concanavalin A; Energy Metabolism; Female; Glucocorticoids; Humans; Leukocytes, Mononuclear; Male; Middle Aged; Oxygen Consumption; Rheumatic Diseases; Treatment Outcome; Virus Diseases

The sensitivity of splenic lymphoid cells to apoptosis induced by low concentrations of methylmercury (MeHgCl) has been examined in C57BL/6 and SJL mice, which are, respectively, resistant and sensitive to a genetically determined autoimmune disease induced by subtoxic doses of MeHgCl. To determine the implications of subtoxic doses of MeHgCl in the susceptibility of SJL mice to autoimmune disease, Concanavalin A (ConA) stimulated spleen cells from both mouse strains were treated in vitro with MeHgCl concentrations varying between 0.001 and 1.0 microM for 48h. Results have shown that ConA-activated splenic lymphoid cells from SJL mice increased in the presence of low concentrations of MeHgCl while the number of lymphoid cells from C57BL/6 mice rather decreased. Flow cytometric analysis of the cells showing a typical lymphoid forward scatter (FSC)/side scatter (SSC) pattern (region R1), and those characterized by a lower FSC and a higher SSC parameters (region R2), morphologically corresponding to apoptotic cells, revealed that lymphoid cells from C57BL/6 mice suffered a dose-dependent shift from region R1 toward region R2 when treated with concentrations ranging between 0.01 and 1 microM of MeHgCl. However, SJL splenic lymphoid cells cultured in the presence of low concentrations of MeHgCl proved more resistant to apoptosis. The level of apoptosis induced by MeHgCl in both regions was verified by AnnexinV-propidium iodide (PI) and TdT-mediated dUTP nick end labeling (TUNEL) immunolabelings. Phenotyping of lymphoid cells from both mouse strains cultured in the presence of low concentrations of MeHgCl and stimulated with ConA, indicated that CD4+ T cells from SJL mice increased while the corresponding cell subset from C57BL/6 mice became apoptotic. The resistance to apoptosis of ConA-activated lymphoid cells from SJL mice seemed related to an increase of CD4+ cells induced by the lower concentrations of MeHgCl (0.001 and 0.01 microM). However, these SJL cells were sensitive to anti-Fas-mediated apoptosis while residual anti-Fas-resistant cells from C57BL/6 mice were, themselves, sensitive to MeHgCl-induced apoptosis. The in vivo significance of these results has been confirmed by an observed increase in splenic cellularity and in the percentage of activated CD4+ cells from SJL mice. These increases were not observed in C57BL/6 mice.

Topics: Animals; Apoptosis; Autoimmune Diseases; CD4-Positive T-Lymphocytes; Concanavalin A; Fas Ligand Protein; fas Receptor; Female; Flow Cytometry; Membrane Glycoproteins; Methylmercury Compounds; Mice; Mice, Inbred C57BL; Spleen

Defects of T cell (Tc) proliferation have been demonstrated in several autoimmune diseases. Detailed mechanisms governing activation and proliferation of Tc are still not completely known. Here we show that under certain conditions human peripheral blood lymphocytes, once activated by anti-CD3, fail to respond to a subsequent restimulation via the Tc-receptor. Peripheral blood mononuclear cells (PBMC) were preactivated by anti-CD3 for 96 h following restimulation by anti-CD3, interleukin (IL)-2 and other mitogens. In control experiments unstimulated PBMC were incubated in medium alone. Immunophenotypes were analysed by flow cytometry. Cytokine production was determined by reverse transcription-polymerase chain reaction and intracellular signalling protein contents of Tc were compared by Western blotting. Furthermore, apoptosis was detected by terminal deoxyribose transferase-mediated deoxyuridine triphosphate nick end labelling assay. Unstimulated PBMC proliferate well after subsequent stimulation with anti-CD3, whereas IL-2 induces only limited proliferation. In contrast, preactivated cells respond only minimally to restimulation with anti-CD3, but IL-2 induces a marked proliferation. Both preactivated and unstimulated Tc respond well to restimulation by phytohaemagglutinin (PHA). In contrast, preactivated Tc show only a weak response to concanavalin A. Interestingly, when cells have been allowed to rest for 168 h, the responsiveness of preactivated Tc is restored. Immunoblots reveal that preactivated cells have a higher intracellular content of zeta-chain and p56lck. No differences are found concerning apoptosis after restimulation with anti-CD3 or the expression of ERK 1/2. The unresponsiveness to restimulation is due to an impairment of the transcription of the IL-2 gene and this defect is temporary. Despite the lack of proliferation, preactivated Tc phenotypically maintain an intermediate stage of activation. These data show how the same cell population can change its functional phenotype into a non-responder state.

Topics: Adaptor Proteins, Signal Transducing; Antibodies, Monoclonal; Apoptosis; Autoimmune Diseases; Carrier Proteins; CD3 Complex; Cell Division; Cells, Cultured; Concanavalin A; Humans; Immediate-Early Proteins; Immune Tolerance; Immunoglobulin gamma-Chains; Interferon-gamma; Interleukin-2; Lymphocyte Activation; Lymphocyte Count; Mitogen-Activated Protein Kinases; Phytohemagglutinins; Proteins; Receptors, Interleukin-2; RNA, Messenger; Sequestosome-1 Protein; T-Lymphocytes; Time Factors

P-selectin (CD62P) is an adhesion molecule that mediates the initial attachment of leukocytes to activated platelets and endothelial cells in damaged tissues. We evaluated the role of P-selectin in concanavalin A (Con A)-induced hepatitis, a model characterized by CD4(+) T cell activation and infiltration of the liver. Con A injection induced transient P-selectin expression on hepatic venules and platelets. Mice lacking P-selectin showed impaired lymphocyte adhesion to liver venules and sinusoids, a striking reduction in intrasinusoidal occlusion, and decreased lymphocyte infiltration of liver parenchyma. The reduction in transaminase levels and the almost complete abolition of necrotic injury demonstrated that liver damage was lower in P-selectin-deficient mice. In wild-type mice, pretreatment with the P-selectin-blocking monoclonal antibody attenuated the sinusoidal occlusion and reduced the rise in transaminases after Con A treatment. These results implicate P-selectin in the development of Con A-induced liver injury and reveal the protective effect of blocking P-selectin in this hepatitis.

Topics: Alanine Transaminase; Animals; Antibodies, Monoclonal; Aspartate Aminotransferases; Autoimmune Diseases; Blood Platelets; CD4-Positive T-Lymphocytes; Cell Adhesion; Chemical and Drug Induced Liver Injury; Chemotaxis, Leukocyte; Concanavalin A; Disease Models, Animal; Endothelium, Vascular; Gene Expression Regulation; Hemostasis; Liver; Mice; Mice, Inbred C57BL; Mice, Knockout; Necrosis; P-Selectin; Specific Pathogen-Free Organisms

Apoptosis of activated lymphocytes is crucial to the maintenance of immune homeostasis and self-tolerance, as demonstrated by the well-known autoimmune MRL lpr mouse lacking the death receptor Fas. However, even MRL+/+ activated T cells have a resistance to Fas-mediated apoptosis as compared to T cells from the non-autoimmune FVB/N strain. To understand the molecular mechanisms underlying these strain differences, we studied biochemical characteristics of T cells upon activation. Compared to FVB/N T cells, MRL T cells under-expressed procaspase-3 but over-expressed FLIP(L). In addition, up-regulation of Bcl-x(L), IL-2, and CD25 was diminished in MRL cells, suggesting inadequate T cell activation. Upon finding that MRL, like other autoimmune strains NOD and SJL, has a hypo-active variant of the IL-2 gene, we added wild-type murine recombinant (mr)IL-2 during activation. Exogenous mrIL-2 restored MRL apoptosis to the level of FVB/N; in addition, expression of procaspase-3, and FLIP(L), Bcl-x(L) and CD25 was normalized. These results suggest that defective MRL T cell activation, in part due to hypo-active IL-2, underlies the impaired apoptosis of this strain. In addition, the hypo-active variant of IL-2 shared among autoimmune strains may, by causing diminished cell activation and cell death, predispose these strains to develop autoimmune disease.

Topics: Amino Acid Sequence; Animals; Apoptosis; Autoimmune Diseases; bcl-X Protein; Carrier Proteins; CASP8 and FADD-Like Apoptosis Regulating Protein; Caspase 3; Caspases; Concanavalin A; Enzyme Induction; Enzyme Precursors; fas Receptor; Gene Expression Regulation; Genotype; Interleukin-2; Intracellular Signaling Peptides and Proteins; Lymphocyte Activation; Mice; Mice, Inbred MRL lpr; Mice, Inbred Strains; Models, Animal; Molecular Sequence Data; Proto-Oncogene Proteins c-bcl-2; Receptors, Interleukin-2; Recombinant Fusion Proteins; Sequence Alignment; Sequence Homology, Amino Acid; T-Lymphocytes

Patients with Crohn's disease (CD) (n = 10) and ulcerative colitis (UC) (n = 10) were tested for immune responses against various antigens from Mycobacterium avium subsp. paratuberculosis; alkyl hydroperoxide reductase C (AhpC) and alkyl hydroperoxide reductase D (AhpD), which are constitutively expressed in this species as opposed to other mycobacteria, a 14-kDa secreted antigen and PPD-J. The CD patients had significantly elevated antibody levels against the 14 kDa protein (P < 0.05) that were negatively correlated with the duration of the disease (r(s) = - 0.85). They also seemed to have increased antibody levels against AhpC and AhpD, but the differences between the two groups were not significant. However, taken together, the antibody responses to three individual mycobacterial antigens in CD patients strengthen the possibility that the observed responses are caused by mycobacterial infection. No significant differences in the interferon (IFN)-gamma production, the interleukin (IL)-10 production and the ability to proliferate upon stimulation with these antigens were observed. These results show that measuring antibody responses against purified specific antigens is a suitable and simple approach when assessing the connection between CD and mycobacteria in patients with clinical CD. Another important aspect in such studies is to have well defined patient groups tested at the onset of clinical symptoms.

Topics: Adult; Antibodies, Bacterial; Antigens, Bacterial; Autoantibodies; Autoimmune Diseases; Colitis, Ulcerative; Concanavalin A; Crohn Disease; Female; Humans; Interferon-gamma; Interleukin-10; Lymphocyte Activation; Male; Middle Aged; Molecular Mimicry; Molecular Weight; Mycobacterium avium subsp. paratuberculosis; Paratuberculosis; Peroxidases; Peroxiredoxins; Phytohemagglutinins; Tuberculin

Both genetic and environmental factors are believed to be involved in the induction of autoimmune diseases. Adjuvant arthritis (AA) is inducible in susceptible rat strains by injection of Mycobacterium tuberculosis, and arthritic rats raise T cell responses to the 65-kDa mycobacterial heat-shock protein (Bhsp65). We observed that Fischer 344 (F344) rats raised in a barrier facility (BF-F344) are susceptible to AA, whereas F344 rats maintained in a conventional facility (CV-F344) show significantly reduced incidence and severity of AA, despite responding well to the arthritogenic determinant within Bhsp65. The acquisition of protection from AA can be circumvented if rats are maintained on neomycin/acidified water. Strikingly, naive unimmunized CV-F344 rats but not BF-F344 rats raised T cell responses to Bhsp65 C-terminal determinants (BCTD) (we have previously shown that BCTD are involved in regulation of acute AA in the Lewis rat); however, T cells of naive CV-F344 and BF-F344 gave a comparable level of proliferative response to a mitogen, but no response at all to an irrelevant Ag. Furthermore, adoptive transfer into naive BF-F344 rats of splenic cells of naive CV-F344 rats (restimulated with BCTD in vitro) before induction of AA resulted in a considerably reduced severity of AA. These results suggest that spontaneous (inadvertent) priming of BCTD-reactive T cells, owing to determinant mimicry between Bhsp65 and its homologues in microbial agents in the conventional environment, is involved in modulating the severity of AA in CV-F344 rats. These results have important implications in broadening understanding of the host-microbe interaction in human autoimmune diseases.

Topics: Adoptive Transfer; Animals; Arthritis, Experimental; Autoimmune Diseases; Bacterial Proteins; Chaperonin 60; Chaperonins; Concanavalin A; Disease Susceptibility; Environment, Controlled; Epitopes, T-Lymphocyte; Housing, Animal; Immunity, Innate; Immunodominant Epitopes; Incidence; Injections, Intraperitoneal; Injections, Intravenous; Intestinal Mucosa; Lymphocyte Activation; Male; Muramidase; Mycobacterium tuberculosis; Peptide Fragments; Rats; Rats, Inbred F344; Severity of Illness Index; Species Specificity; Spleen; T-Lymphocytes

We have previously reported that cluster of differentiation (CD)4+ T cells induced autoimmune liver diseases in mice with graft-versus-host reaction (GVHR) because of major histocompatibility complex (MHC) class II disparity. To analyze the progression of the autoimmune-related mechanism in the liver, concanavalin A (Con A) was injected in mice undergoing GVHR. The aim of this study is to clarify whether Con A deteriorates murine hepatic lesions induced by GVHR, and to elucidate the participation of the cytokines of liver-infiltrating CD4+ T cells.. Mice (F1; B6.C-H-2(bm12) x B6) were intravenously injected with B6 T spleen cells. Concanavalin A (15 mg/kg) was administrated 5 days after cell transfer. We examined serum transaminase, antimitochondrial antibodies (AMA), antinuclear antibodies (ANA) and histological changes. Liver-infiltrating CD4+ T cells were sorted and their cytokine mRNA expression was examined by the use of reverse transcription-polymerase chain reaction (RT-PCR).. Graft-versus-host reaction + Con A mice revealed an elevated serum transaminase, elevated AMA and ANA titers, increased periportal cellular infiltration, piecemeal necrosis and bridging necrosis in the liver. In this group, interferon (IFN)-gamma mRNA expression was more elevated than it was in the GVHR mice. However, there was no difference in the expression of interleukin (IL)-10 mRNA between the two groups.. The results suggest that Con A deteriorates the GVHR-induced hepatic lesions, and IFN-gamma and IL-10 of CD4+ T cells might be implicated in the progression of autoimmune-related hepatic lesions. This model might offer an aspect for the investigation of progressive mechanisms in T-cell- mediated hepatobiliary injury.

Topics: Analysis of Variance; Animals; Autoantibodies; Autoimmune Diseases; CD4-Positive T-Lymphocytes; Cell Transplantation; Concanavalin A; Cytokines; Disease Models, Animal; Graft vs Host Disease; Hepatitis; Liver Function Tests; Mice; Mice, Inbred C57BL; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Spleen

The chimeric cell surface receptor scC2Fv/CD8/zeta was constructed to engineer primary mouse T lymphocytes with antibody-type specificity to type II collagen (CII). Such cells could be used as gene carriers in the anti-inflammatory gene therapy of an autoimmune arthritis. This receptor includes the single chain Fv domain (scFv) of the anti-CII monoclonal antibody (mAb) C2, hinge region of CD8alpha and the transmembrane and cytoplasmic domains of TCRzeta. The scC2Fv/CD8/zeta gene was transduced into T cell hybridomas and primary mouse lymphocytes using retrovirus-mediated gene transfer. The chimeric receptor scC2Fv/CD8/zeta forms covalently bound homodimers, as demonstrated in T cell hybridomas and packaging fibroblasts. It does not associate with endogenous signalling subunits of the TCR complex. When scC2Fv/CD8/zeta-expressing clones of T cell hybridomas MD.45 and HCQ6 were stimulated with CII they produced IL-2. The level of their IL-2 response correlated with the expression level of the chimeric receptor on the cell surface. Splenocytes isolated from DBA/1 mice were stimulated with Con A in vitro to facilitate retrovirus-mediated transfer of the scC2Fv/CD8/zeta gene. As a result of transduction, approximately 4% of the Con A-activated splenocytes expressed the chimeric receptor scC2Fv/CD8/zeta on the cell surface. These cells proliferated in response to stimulation with CII.

Topics: Animals; Arthritis; Autoimmune Diseases; Collagen; Concanavalin A; Genetic Therapy; Hybridomas; Immunoglobulin Fragments; Interleukin-2; Membrane Proteins; Mice; Mice, Inbred DBA; Receptors, Antigen, T-Cell; Stimulation, Chemical; T-Lymphocytes; Transfection

A study was made of the behavior of peripheral blood lymphocytes in healthy controls and patients with various types of hearing loss. Hearing loss of auto-immune origin was studied in the presence and absence of melatonin, activated or not by concanavalin A. In patients with auto-immune hearing loss, lymphocytes showed hyporeactivity to type II collagen in terms of proliferative activity in the presence of concavalin A. Hyporeactivity was especially relevant in melatonin-incubated cells. In different nosologic entities, lymphocyte hyporeactivity to type II collagen was similar in bilateral sensorineural hearing loss, Ménière's disease and otosclerosis. We conclude that the lymphocytes of patients with autoimmune hearing loss showed hyporeactivity to type II collagen when compared to lymphocytes from control subjects. This hyporeactivity was revealed when lymphocytes were activated in the presence of melatonin.

Topics: Adolescent; Adult; Aged; Autoimmune Diseases; Cell Movement; Collagen; Concanavalin A; Deafness; Female; Humans; Lymphocytes; Male; Melatonin; Meniere Disease; Middle Aged; Pineal Gland

To investigate the interaction and adherence of inflammatory cells to a heparin-surface-modified intraocular lens (HSM IOL).. Department of Ophthalmology, Tokyo Medical University Hospital, Tokyo, Japan.. Splenic mononuclear leukocytes from rats with experimental autoimmune uveitis were cultured with the optic of an HSM IOL for 96 hours. The number of adherent cells on the HSM IOL surface was measured with and without the addition of interphotoreceptor retinoid-binding protein and concanavalin A (ConA) to the culture medium. The adherent cells were observed under a light microscope or a scanning electron microscope.. Interphotoreceptor retinoid-binding protein and ConA increased the number of adherent cells on the HSM IOL relative to the control. Adherent cells on the HSM IOL were small and round, considered to be mainly lymphocytes.. Activated lymphocytes tended to adhere to the surface of the HSM IOL.

Topics: Animals; Autoimmune Diseases; Cell Adhesion; Cells, Cultured; Coated Materials, Biocompatible; Concanavalin A; Disease Models, Animal; Eye Proteins; Fibrinolytic Agents; Heparin; Lenses, Intraocular; Polymethyl Methacrylate; Rats; Rats, Inbred Lew; Retinol-Binding Proteins; Spleen; Surface Properties; Uvea; Uveitis, Anterior

To investigate the role of nitric oxide (NO), produced by the inducible form of NO synthase (NOS-2) in the development of experimental autoimmune uveoretinitis (EAU), we immunized C57BL/6x129Sv (H-2(b)) mice carrying a targeted disruption of the gene encoding NOS-2 (NOS-2[-/-]), and wild-type (WT) C57BL/6x129Sv controls with interphotoreceptor retinoid binding protein (IRBP). NOS-2[-/-] mice developed a clinical EAU with delayed onset and decreased severity compared to WT controls. The ocular tissues from WT mice contained activated F4/80 macrophages with NOS-2 expression and retinal destruction whereas less intense EAU was detected in NOS-2[-/-] mice. The expression of NOS-2 mRNA was detected in the retina at the peak of EAU in WT. Analysis of cytokine production in the spleen from NOS-2[-/-] mice by RT-PCR showed high levels of IL-10 mRNA. Our results demonstrate that NO is clearly involved in EAU and may be important for the regulation of immune responses through the regulation of IL-10.

Topics: Animals; Autoimmune Diseases; Cell Division; Concanavalin A; Eye Proteins; Female; Gene Expression Regulation, Enzymologic; Immunization; Immunoglobulin G; Interferon-gamma; Interleukin-10; Lymphocytes; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Retina; Retinitis; Retinol-Binding Proteins; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Severity of Illness Index; Spleen; Tumor Necrosis Factor-alpha; Uveitis

UK-114 is a 14-kDa ubiquitous protein recently sequenced by several groups throughout the world. Its activity ranges from being a tumor antigen, a protein synthesis inhibitor or a specific mu-calpain activator. UK-114 shows structural homologies also with proteins of the MHC-1 binding proteins, and heat shock proteins (HSPs). We investigated the possible effects of UK-114 on T helper cells cytokine profile and the development and progression of experimental autoimmune diseases. Homogeneous recombinant UK-114 was used in all experiments. Treatment of Balb/c male mice for two weeks resulted in the increase of IL-4, and the decrease of TNF-alpha, IFN-gamma, and IL-2 release from stimulated splenocytes, suggesting that UK-114 modulates the Th1/Th2 cytokine profile toward Th2. Similar to that observed with HSP60/65, a single pretreatment of Lewis rats with UK-114 significantly blunted the development of adjuvant-induced arthritis, whereas chronic treatment of 4-week-old female NOD mice dose dependently inhibited the development of diabetes.

Topics: Animals; Autoimmune Diseases; Concanavalin A; Cytokines; Diabetes Mellitus, Type 1; Female; Interferon-gamma; Male; Mice; Mice, Inbred BALB C; Mice, Inbred NOD; Neoplasm Proteins; Rats; Rats, Inbred Lew; Th1 Cells; Th2 Cells; Time Factors

Cyclosporin A-induced autoimmunity (CsA-AI) is a T-cell mediated inflammatory autoimmune disease of the skin resembling human scleroderma and is often referred to as syngeneic-Graft-versus-Host Disease. Induction of CsA-AI is obtained by total body irradiation in combination with syngeneic bone marrow transplantation (BMT) and subsequent administration of CsA for 4 weeks; about 2 weeks after withdrawal of CsA disease develops. In CsA-AI, irradiation is thought to eliminate peripheral autoregulatory T-cells, whereas CsA interferes with selection in the thymus giving rise to putative autoreactive T-cells. MHC class II-self-peptide complexes have been thought to function as autoantigen(s). Moreover, induction of CsA-AI is used in humans to achieve a Graft-versus-Leukemia effect based on this anti-MHC class II reactivity. In this study we therefore have examined whether T-cells of CsA-AI rats respond to syngeneic dendritic cells (DC). Furthermore we determined the in vitro stimulatory capacity of the presumptive antigen presenting cell (APC) in the target organs, i.e. the keratinocytes. In contrast to keratinocytes of control rats the keratinocytes of CsA-AI rats show in situ a strong reactivity with anti-MHC class II specific monoclonal antibody (mAb) and therefore might induce local T-cell activation. Results reveal that T-cells of CsA-AI rats have no increased response to syngeneic DC. This indicates that MHC class II is not the autoantigen and that the autoantigen(s) are not presented by peripheral APC of control animals. With respect to possible APC in the target organ flow cytometry showed a strong induction of MHC class II and upregulation of MHC class I on keratinocytes of CsA-AI rats. However, these cells were unable to give any stimulatory signal to T-cells of control or diseased animals, indicating that the autoantigen(s) are not presented by keratinocytes of CsA-AI rats and that the MHC induction is probably secondary to the inflammatory reaction in the skin. The nature of the autoantigen(s) therefore remains to be determined.

Topics: Animals; Antigen-Presenting Cells; Autoimmune Diseases; Autoimmunity; Cell Division; Concanavalin A; Cyclosporine; Disease Models, Animal; Histocompatibility Antigens Class I; Histocompatibility Antigens Class II; Immunosuppressive Agents; Keratinocytes; Mitogens; Rats; Rats, Inbred Lew; T-Lymphocytes

The mechanism of action of recombinant IFNbeta1b (IFNbeta-1b), as a therapy for multiple sclerosis (MS), is still unknown but may result from the enhancement of ConA-induced suppressor cell function and the inhibition of IFNgamma secretion by lymphocytes. We previously demonstrated that IFNbeta-1b stimulated modest amounts of IL-10 secretion by monocytes and IL-10 activity, as cytokine synthesis inhibitory factor, was normal in MS. To determine whether IL-10 plays a role in IFNbeta-1b modulation of immune function in MS, we studied ConA-induced suppressor cell function and IFNgamma production in presence of IFNbeta-1b and an anti-IL-10 monoclonal antibody (mAb). Anti-IL-10 mAb significantly reduced the effect of IFNbeta-1b on ConA-induced suppressor cell function and IFNgamma production in healthy subjects; MS patients showed a trend of inhibition. We hypothesized that IL-10 may play a role in mediating the effects of IFNbeta-1b on suppressor cell function and IFNgamma production but suppressor molecules other than IL-10 could be also involved.

Topics: Adult; Antibodies, Monoclonal; Autoimmune Diseases; Cells, Cultured; Concanavalin A; Drug Interactions; Female; Humans; Immunologic Factors; Interferon beta-1a; Interferon beta-1b; Interferon-beta; Interleukin-10; Lymphocyte Activation; Male; Multiple Sclerosis; Recombinant Fusion Proteins; T-Lymphocytes, Regulatory

To quantify S-antigen-specific (S-Ag) T cells in the retina after adoptive transfer, and to evaluate their role in the initiation and progress of destructive ocular inflammation in experimental autoimmune uveoretinitis (EAU).. Lewis rats were administered 10 x 10(6) S-Ag-specific T cells from the SP35 cell line or 10 x 10(6) concanavalin A-stimulated syngeneic spleen cell lymphoblasts labeled with lipophilic PKH26 fluorescent dye immediately before intravenous inoculation. Labeled cells in each retina were counted at various times from 4 to 120 hours after cell transfer by fluorescence microscopic analysis of each dissociated retina. Recipient eyes were examined within the same period by light and confocal microscope.. SP35 T cells showed a biphasic distribution in the retina. The first peak of 160 cells/retina was noted at 24 hours. A steady decline of labeled cells at 48 and 72 hours was followed by a rapid increase at 96 and 120 hours. Concanavalin A-stimulated, control-labeled cell populations showed an identical peak at 24 hours but a persistent decline thereafter; only two or three T cells were present in each retina at 120 hours. Concurrent inoculation of SP35 cells and nonspecific T cell blasts did not produce more SP35 cells than control cells in the retina at any time. Microscopic analysis showed mononuclear cell infiltration of the iris, ciliary body, and aqueous humor at 48 hours, which intensified rapidly and persisted through 120 hours. Retinal inflammation did not begin until 80 hours. Mononuclear cell adherence to vascular endothelium and perivascular macrophage infiltration of the innermost layers progressed to edema, and profound destructive inflammation and loss of retinal stratification were observed at 120 hours.. There is no evidence of a blood-ocular or blood-retinal barrier to activated T cell blasts. Autologous S-Ag does not provoke a more rapid entry of specific T cells at that site. The data confirm that anterior segment inflammation precedes retinal inflammation, even though S-Ag-specific T cells were present in the retina within a few hours after cell transfer. Because S-Ag is clearly present in the retina, delay in antigen presentation at that site may account for the temporal difference between retinal and anterior segment inflammation.

Topics: Adoptive Transfer; Animals; Arrestin; Autoimmune Diseases; Concanavalin A; Cytokines; Disease Models, Animal; Fluorescent Dyes; Lymphocyte Activation; Lymphocyte Count; Male; Organic Chemicals; Rats; Rats, Inbred Lew; Retina; Retinitis; T-Lymphocytes; Uveitis, Anterior; Uveitis, Posterior

MX-68 is a novel antifolate which is chemically designed not to undergo intracellular polyglutamation thus preventing the development of adverse effects. The present study was carried out to examine both the in vitro and in vivo effects of MX-68 on experimental autoimmune uveitis (EAU) and to compare its effect on collagen-induced arthritis (CIA) in rats. EAU was induced by injecting Lewis rats with retinal S-antigen in complete Freund's adjuvant. Either MX-68 or methotrexate (MTX), which forms several polyglutamates intracellularly, was orally administered five days a week for three weeks beginning on the day of immunization. In vivo, both MX-68 and MTX significantly delayed the onset of EAU and inhibited the antibody response to S-antigen in a dose-dependent manner. High dose MX-68 (2.5 mg kg-1 day-1) completely abrogated the induction of EAU. No adverse effects were observed in either MX-68- or MTX-treated rats. However, the cessation of MX-68 administration after a period of three weeks resulted in the induction of EAU. In contrast, both MX-68 and MTX suppressed the severity of CIA without affecting the onset of the disease and inhibited anti-collagen antibody production in a dose-dependent fashion. Discontinuation of the drugs did not result in the recurrence of CIA. In vitro, both MX-68 and MTX significantly suppressed the proliferation of S-antigen- and Con A-stimulated lymph node cells obtained from immunized rats in a dose-dependent fashion. These data suggest that MX-68 may be useful for the treatment of autoimmune diseases including EAU and that the pathophysiology of EAU could be different from that of CIA.

Topics: 2-Aminoadipic Acid; Animals; Arrestin; Arthritis, Experimental; Autoimmune Diseases; Cell Division; Cells, Cultured; Collagen; Concanavalin A; Dose-Response Relationship, Drug; Female; Folic Acid Antagonists; Immunization; Immunosuppressive Agents; Lymphocytes; Methotrexate; Rats; Rats, Inbred Strains; Uveitis

Although autoreactive T cells recognizing self myelin Ags are present in most individuals, autoimmune disease of the central nervous system is a relatively rare medical condition. Development of autoimmune disease may require not only the presence of autoreactive T cells but also that autoreactive T cells become activated. Activation of T cells may require a minimum of two signals: an Ag-specific signal delivered by MHC-peptide complex and a second signal delivered by costimulatory molecules or cytokines. Although in vitro studies have suggested that cytokines, especially proinflammatory cytokines such as IL-1, IL-6, and TNF are involved in T cell activation, their precise roles in vivo are not clear. To determine the roles of proinflammatory cytokines in T cell activation in vivo and in the development of autoimmune disease, we have studied experimental autoimmune encephalomyelitis (EAE) in mice deficient in IL-6. We found that IL-6-deficient mice were completely resistant to EAE induced by myelin oligodendrocyte glycoprotein (MOG), whereas IL-6-competent control mice developed EAE characterized by focal inflammation and demyelination in the central nervous system and deficiency in neurologic functions. Furthermore, we established that the resistance to EAE in IL-6-deficient mice was associated with a deficiency of MOG-specific T cells to differentiate into either Th1 or Th2 type effector cells in vivo. These results strongly suggest that IL-6 plays a crucial role in the activation and differentiation of autoreactive T cells in vivo and that blocking IL-6 function can be an effective means to prevent EAE.

Topics: Animals; Autoimmune Diseases; Autoimmunity; Cell Differentiation; Concanavalin A; Disease Progression; Encephalomyelitis, Autoimmune, Experimental; Immunity, Innate; Immunization; Interleukin-6; Lymphocyte Activation; Mice; Mice, Knockout; Myelin Proteins; Myelin-Associated Glycoprotein; Myelin-Oligodendrocyte Glycoprotein; Ovalbumin; T-Lymphocyte Subsets

Previous studies have shown that the administration of concanavalin A (ConA) into mice induces immune-mediated liver injury, which can be largely abrogated by neutralizing tumor necrosis factor(TNF)alpha. Vesnarinone is an experimental drug which is known to inhibit TNF alpha release. Here we demonstrate that vesnarinone inhibits ConA-induced hepatic injury. In a dose-dependent manner, vesnarinone inhibits in several mouse strains the increase of serum aminotransferase concentrations. additional experiments show that vesnarinone inhibits ConA-mediated accumulation of DNA fragmentation in the liver. Furthermore, the drug significantly reduces the levels of circulating TNF alpha and interleukin-6 (IL-6). Vesnarinone does not modulate TNF alpha and IL-6 action on hepatic cells, as shown by its failure to reduce the cytokine specific-stimulation of acute phase plasma proteins in the rat hepatoma H-35 cell line. Neither vesnarinone nor anti-TNF alpha protect against direct liver injury induced by a sublethal dose of agonist anti-Fas (CD95) antibody. Taken together, these results suggest that vesnarinone blocks hepatic injury, in part by inhibiting the release of TNF alpha in vivo.

Topics: Acute-Phase Reaction; Animals; Antibodies, Monoclonal; Autoimmune Diseases; Chemical and Drug Induced Liver Injury; Concanavalin A; fas Receptor; Liver Neoplasms, Experimental; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Pyrazines; Quinolines; Rats; Tumor Cells, Cultured; Tumor Necrosis Factor-alpha

We have studied the behavior of peripheral blood lymphocytes in healthy controls and in patients with various hearing losses. These hearing losses were of an autoimmune origin in which type II collagen and melatonin were either present or absent, activated or not with concanavalin A (Con A). In patients with autoimmune hearing losses, the results showed lymphocytes that displayed hyporeactivity to type II collagen in terms of their proliferative activity in the presence of Con A. The hyporeactivity is specially relevant in those cells which are melatonin incubated. When different nosologic entities were studied, we observed similar lymphocyte hyporeactivity to type II collagen in bilateral sensorineural hearing loss, Ménière's disease and otosclerosis. We conclude that in the lymphocytes of patients with autoimmune hearing losses, there is hyporeactivity to type II collagen when compared to the hyporeactivity of lymphocytes in control groups. This hyporeactivity is revealed when the lymphocytes are activated in the presence of melatonin.

Topics: Adolescent; Adult; Aged; Autoimmune Diseases; Case-Control Studies; Cell Division; Child; Collagen; Concanavalin A; Deafness; Female; Humans; Lymphocytes; Male; Melatonin; Meniere Disease; Middle Aged; Otosclerosis

MS is presumed to be a T-cell-mediated chronic inflammatory disease of the CNS. We examined proliferation and cytokine secretion of mononuclear cells after stimulation with OKT3 [anti-CD3] monoclonal antibody (MAb) or concanavalin A (Con A) in subjects with stable relapsing-remitting MS (RR MS) before and after initiating interferon (IFN)-beta 1b treatment. There was no significant difference in pretreatment to on-treatment anti-CD3 mAb or Con A-induced proliferation in RR MS patients. There was significantly increased Con A-induced secretion of tumor necrosis factor (TNF)-alpha, IFN-gamma, interleukin (IL)-2, IL-6, and IL-10 and decreased IL-4 secretion in on-treatment compared with pretreatment peripheral blood mononuclear cell samples. However, on-treatment CD3-mediated secretion of TNF-alpha was significantly decreased, and IL-6 secretion was significantly increased compared with pretreatment values. IFN-gamma was also decreased in on-treatment cultures stimulated with anti-CD3 MAb, but these values did not reach statistical significance. Systemic side effects from IFN-beta 1b were associated with increased IL-6 secretion. There were no significant changes in CD3-mediated IL-4, IL-10, transforming growth factor (TGF)-beta, or IL-2 secretion or Con A-induced TGF-beta secretion. IFN-beta 1b (Betaseron) decreases CD3-mediated TNF-alpha secretion but increases another inflammatory cytokine, IL-6, that could potentially counteract its beneficial immunomodulatory effects.

Topics: Autoimmune Diseases; Concanavalin A; Humans; Immunologic Factors; Interferon beta-1a; Interferon beta-1b; Interferon-beta; Interferon-gamma; Interleukin-10; Interleukin-2; Interleukin-4; Interleukin-6; Lymphocyte Activation; Multiple Sclerosis; Muromonab-CD3; Recombinant Proteins; T-Lymphocytes, Cytotoxic; Tumor Necrosis Factor-alpha

Interleukin-2 (IL-2) was demonstrated to induce interferon (IFN) production in the cultured lymphocytes from healthy donors and myasthenia gravis (MG) patients. Moreover, IL-2 enhanced lymphocytic IFN production in patients and healthy individuals in response to phytohemagglutinin and concanavalin A. However, in MG patients, IFN production in response to IL-2 alone or in combination with mitogens is several times lower than that in healthy donors. This lowered IFN production in MG patients is accompanied by much higher rates of lymphocytic proliferation and by considerably enhanced spontaneous lymphocytic production of C-reactive protein as compared with healthy individuals. This test may be of great value in establishing the diagnosis of an autoimmune disease, in defining its severity and in evaluating the efficiency of therapy.

Topics: Autoimmune Diseases; C-Reactive Protein; Cell Division; Cells, Cultured; Concanavalin A; Humans; Interferons; Interleukin-2; Lectins; Lymphocyte Activation; Lymphocytes; Mitogens; Myasthenia Gravis; Phytohemagglutinins; Recombinant Proteins

Chronic relapsing experimental allergic encephalomyelitis (CR.EAE) was induced by immunizing Lewis rats with total guinea-pig spinal cord (GPSC) tissue emulsified in enriched complete Freund's adjuvant (CFA). The proliferative responses of draining inguinal and popliteal lymph node cells to GP.MBP, purified protein derivative (PPD) and concanavalin A (ConA) appeared significantly modulated according to the clinical state of the animals. Responses appeared significantly decreased in both lymphoid compartments during the recovery periods compared with that during relapses. Therapeutic treatment of CR.EAE with cyclosporin and different lysolecithin derivatives, such as ET-18-OCH3, SRI 62-843 and MLS 266-337, starting at the spontaneous remission of the first disease bout, could suppress the manifestation of further relapses. Whereas cyclosporin only delayed the onset of the disease relapse until discontinuation of treatment, all lysolecithins showed a curative effect in most animals. Plasma corticosterone levels measured at different time points in placebo, cyclosporin and MLS 266-377-treated rats showed a strong correlation with the clinical state of the animals. High corticosterone levels were detected during stages of acute paralysis, whereas a decrease to normal levels was noted during each recovery phase.

Topics: Animals; Autoimmune Diseases; Concanavalin A; Corticosterone; Cyclosporine; Dexamethasone; Disease Models, Animal; Encephalomyelitis, Autoimmune, Experimental; Female; Furans; Guinea Pigs; Lymph Nodes; Lymphocyte Activation; Lysophosphatidylcholines; Multiple Sclerosis; Myelin Basic Protein; Phospholipid Ethers; Rats; Rats, Inbred Lew; Tuberculin

We previously reported that difluoromethylornithine (DFMO), an inhibitor of polyamine biosynthesis, exerted significant beneficial effects on the lifespan and disease expression of MRL-lpr/lpr mice, which spontaneously develop a lupus-like syndrome. Polyamine levels in splenic T-cells of MRL-lpr/lpr mice were significantly higher than those of Balb/c mice. In the present investigation, we examined the role of endogenous polyamines in transmembrane Ca2+ influx, generation of InsP3 and tyrosine phosphorylation of the p56lck protein in concanavalin A-stimulated splenic T-cells. Cytosolic free calcium concentrations ([Ca2+]i) in concanavalin A-stimulated T-cells of MRL-lpr/lpr and Balb/c mice were 250 +/- 25 and 450 +/- 42 nM respectively. Treatment of MRL-lpr/lpr mice with DFMO increased [Ca2+]i to 360 +/- 30 nM (P < 0.05). InsP3 levels of concanavalin A-stimulated MRL-lpr/lpr splenic T-cells were only 20% higher than those of unstimulated controls, whereas those of Balb/c T-cells were 90% higher. DFMO treatment increased InsP3 levels in concanavalin A-treated MRL-lpr/lpr T-cells to 67%. Western-blot analysis showed a 7-fold higher level of p56lck phosphorylation of MRL-lpr/lpr splenic T-cells than that of Balb/c mice. DFMO treatment reduced tyrosine phosphorylation of p56lck of MRL-lpr/lpr mice significantly (P < 0.001). Two-colour flow-cytometric analysis revealed no significant difference in the CD4+/CD8+ ratio in splenic T-cells of MRL-lpr/lpr mice after DFMO treatment. Polyamine levels in splenocytes were significantly reduced by DFMO treatment. These data show that DFMO treatment could alter signal-transduction pathways of splenic T-cells of MRL-lpr/lpr mice. Increased levels of polyamines in T-cells of untreated lpr mice contribute to defective signal-transduction pathways and the pathogenesis of lupus-like symptoms.

Topics: Animals; Autoimmune Diseases; Blotting, Western; Calcium; CD4-CD8 Ratio; Concanavalin A; Eflornithine; Female; Inositol Phosphates; Lupus Erythematosus, Systemic; Mice; Mice, Inbred BALB C; Ornithine Decarboxylase; Phosphorylation; Phosphotyrosine; Polyamines; Signal Transduction; Spleen; T-Lymphocytes

(NZB x NZW)F1 (B/W) mice spontaneously develop a lupus-like syndrome characterized by an increased level of autoantibodies in old mice. We analysed the role of T cells in the regulation of anti-DNA antibody production by B cells in vitro as a function of age. In cultures of old mouse T and B cells, IgG and IgM anti-DNA antibodies were synthesized at high levels, in contrast to consistently lower amounts, particularly of IgG, measured in cultures of young mouse cells. Addition of young mouse T cells to old B cells inhibited IgG, but not IgM, anti-DNA production, whereas T cells from old mice stimulated IgG synthesis by young mouse B cells. Addition of supernatants harvested from concanavalin A (Con A)-stimulated T cells to B-cell cultures induced similar effects. Therefore, we evaluated possible modifications of lymphokine synthesis compared to that of the healthy NZW parent. T cells from old mice were able to secrete normal levels of interferon-gamma (IFN-gamma) and interleukin (IL)-10; however, secretion of IL-2 and IL-4 was dramatically decreased. Semi-quantitative polymerase chain reaction analysis of constitutive RNA messengers showed increased IFN-gamma levels in young and old B/W mice, and normal IL-10 mRNA levels in young and higher levels in old mice. Constitutive IL-2 and IL-4 mRNA were detected only after Con A stimulation and their levels decreased in old compared to young B/W mice; in particular IL-2 mRNA was considerably lower in old B/W than in control NZW mice. Taken together, these results suggest that, despite constitutive T-cell abnormalities, young B/W mice are able partially to control their lymphokine production, whereas aged mice exhibit a deficient synthesis, associated with an increased capacity to produce IFN-gamma.

Topics: Aging; Animals; Antibodies, Antinuclear; Autoimmune Diseases; Cells, Cultured; Concanavalin A; Culture Media, Conditioned; Female; Gene Expression; Immunoglobulin G; Immunoglobulin M; Lupus Erythematosus, Systemic; Lymphokines; Male; Mice; Mice, Inbred NZB; RNA, Messenger; T-Lymphocytes

Brown Norway (BN) rats are poor responders to T-cell mitogens and alloantigens when compared to Lewis (LEW) rats. This is dependent partly upon a defect in IL-2 production. The TH2-mediated immune abnormalities observed in BN rats injected with mercuric chloride (HgCl2) are self-limited and it is probable that this regulation phase involves TH1-like cells. This paper reports on a study of the ability of lymph node cells (LNC) from normal BN and LEW rats and from HgCl2-injected BN rats to produce IL-2 and to proliferate when stimulated in vitro by Con A or alloantigens in mixed lymphocyte reaction (MLR), as well as to develop a cytotoxic T lymphocyte (CTL) response to alloantigens. This study will confirm that LNC from BN rats proliferate less than LNC from LEW rats, that the former produce less IL-2 than the latter, and that the proliferative response is restored partially after addition of IL-2. In addition, it is shown (1) that the CTL response is defective in normal BN rats when compared to that of normal LEW rats, and (2) that, after the second week of HgCl2 injections, the proliferative responses to Con A and alloantigens are improved as well as IL-2 production, and a complete restoration of CTL function is observed. These results show that normal BN rats are deficient in the induction of TH1-like cells and that, from the second week of HgCl2 injections, these TH1 functions improve.

Topics: Animals; Autoimmune Diseases; CD4-Positive T-Lymphocytes; Concanavalin A; Female; Interleukin-2; Isoantigens; Lymphocyte Activation; Lymphocyte Culture Test, Mixed; Male; Mercuric Chloride; Rats; Rats, Inbred BN; Rats, Inbred Lew; T-Lymphocyte Subsets; T-Lymphocytes, Cytotoxic

The in vitro and in vivo effects of a new immunomodulating agent, bucillamine, on experimental autoimmune uveitis (EAU) was studied in the rat. The capacity of S-antigen-sensitized lymphocytes to proliferate in response to the antigen or to produce antigen-specific antibodies was significantly suppressed by bucillamine in culture in a dose-dependent manner. The inhibitory effect of bucillamine was significantly enhanced by adding cyclosporin A (CYA) in the culture. The in vivo effects of bucillamine alone or in combination with CYA were further examined in Lewis rats immunized with S-antigen. All untreated rats developed severe EAU 17 days after S-antigen immunization, while rats treated with either bucillamine (200 mg kg-1 day-1) or CYA (2 mg kg-1 day-1) demonstrated milder symptoms of EAU. A combination therapy with bucillamine (20 or 200 mg kg-1 day-1) and CYA (2 mg kg-1 day-1) exhibited much more significant suppression of EAU induction. Although the in vivo treatment with bucillamine or CYA had no effects on the T-cell populations of spleen cells, the combination therapy significantly decreased the CD4+ T-cell population. As for the immune responses to S-antigen in drug-treated rats, bucillamine suppressed the lymphocyte proliferation to S-antigen, which was further suppressed by combination therapy with CYA. The serum antibody levels specific to S-antigen were not affected by tested dose of bucillamine.

Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Antibody Formation; Antigens; Arrestin; Autoimmune Diseases; Cell Division; Cells, Cultured; Concanavalin A; Cyclophosphamide; Cysteine; Drug Synergism; Eye Proteins; Immune Tolerance; Male; Rats; Rats, Inbred Lew; Spleen; Uveitis

Diabetes-prone (DP) BB rats spontaneously develop a hyperglycaemic condition which closely resembles human insulin-dependent diabetes mellitus (IDDM), both in terms of clinical and histological features. The incidence of IDDM was significantly reduced when these animals were treated with 2 or 4 mg fusidic acid (FA)/day i.m. from day 30 to day 120 of age. In addition, the mean insulitis score was significantly diminished in the animals treated with FA compared to both vehicle-treated and untreated controls. Finally, 2 mg/day of FA i.m. prevented cell proliferation and interferon-gamma secretion from peripheral blood mononuclear cells upon ex vivo stimulation with concanavalin A. The capacity of FA to substantially reduce the incidence of autoimmune diabetes in a well-known animal model of human IDDM supports previous observations regarding the immunosuppressive properties of FA and its potential use in the treatment of human autoimmune diabetes.

Topics: Age Factors; Animals; Autoimmune Diseases; Cell Division; Cells, Cultured; Concanavalin A; Diabetes Mellitus, Type 1; Female; Fusidic Acid; Interferon-gamma; Islets of Langerhans; Male; Rats; Rats, Inbred BB; T-Lymphocytes

Lymph nodes, spleen and thymus obtained from Lewis rats were examined over the course of experimental autoimmune myasthenia gravis (EAMG) for the distribution and the number of antigen-reactive CD4+ T helper cells which, upon recognition of Torpedo acetylcholine receptor (AChR) or the alpha, beta, gamma or delta subunits of Torpedo AChR, responded by secretion of interferon-gamma (IFN-gamma). T cells with these specificities were detected in these three immune organs. Numbers were highest in lymph nodes. In spleen and thymus, numbers of antigen-reactive T cells did not differ. T cells reacting against the intact AChR were more frequent than T cells recognizing any of the subunits. The immunogenicity between the four subunits did not differ, with the exception that the alpha subunit induced a slightly higher T-cell response. No restriction of the T-cell repertoire to the four subunits was detected during early compared to late phases of EAMG. The AChR and subunit-reactive T cells could--via secretion of effector molecules including IFN-gamma--play an important role in the initiation and perpetuation of EAMG, and consequently also of human myasthenia gravis. T cells with the same specificities were also detected in control animals injected with adjuvant only, but at much lower numbers which were within the range of T cells recognizing the control antigen myelin basic protein. They could represent naturally occurring autoimmune T cells.

Topics: Animals; Autoimmune Diseases; Concanavalin A; Disease Models, Animal; Electrophoresis, Polyacrylamide Gel; Epitopes; Female; Interferon-gamma; Lymph Nodes; Lymphocyte Activation; Myasthenia Gravis; Peptide Fragments; Rats; Rats, Inbred Lew; Receptors, Cholinergic; Spleen; T-Lymphocytes; Thymus Gland

Previous studies from this and other laboratories have shown that abnormal glycosylation of several acute-phase proteins can be detected in various pathological conditions including autoimmune diseases. In the present study, we have investigated if abnormal glycosylation is limited to acute-phase proteins. We used the concanavalin A (Con A) blots in conjunction with the peptide mapping techniques to analyze serum samples and cerebrospinal fluids (CSF) obtained from patients with autoimmune diseases: systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), mixed connective tissue disease (MCTD), scleroderma (SCL), Sjögren's syndrome (SS), and polymyositis (PM); diseases of probable autoimmune origin: hepatopathies (HP); diseases of suspected autoimmune origin: schizophrenia and Alzheimer's disease (AZ); and conditions not related to autoimmunity: pregnancy (PG) and elevation of the carcinoembryonic antigen (CEA), in comparison to normal donors (NHS). We have micropurified two human proteins; alpha 2-macroglobulin, a non-acute-phase protein and beta-chain of haptoglobin, a known acute-phase protein, from serum samples of individual patients with SLE, RA, MCTD, SCL and SS, and from PG and NHS for analysis. The identity of the purified proteins was confirmed by immunoblots using either monospecific polyclonal or monoclonal antibodies, and by direct N-terminal amino acid sequencing. Peptide maps for each of these proteins were generated using Staphylococcus aureus protease V8, a Glu-C endopeptidase. When the peptide fragments of alpha 2-macroglobulin were resolved by SDS-PAGE and visualized using silver staining, no differences were noted between patient samples and controls. However, when they were examined by lectin blots using Con A, the Con A-reactive fragments increased specifically and significantly in samples derived from patients of SLE, SCL, MCTD, and RA. Similarly when the peptide fragments of the beta-chain of haptoglobin were visualized by silver staining, no differences were noted; however, the Con A reactivity of specific fragments increased in SLE, RA, SCL, and SS patients. Analysis of these results indicated that there has been a selective increase in Con A-reactive fragments in both acute-phase and non-acute-phase proteins in autoimmune conditions. Thus, the study of changes in glycosylation patterns in selected serum proteins may be a valuable diagnostic approach to define the pathophysiology of inflammatory and autoimmune disorders.

Topics: Acute-Phase Proteins; alpha-Macroglobulins; Amino Acid Sequence; Autoimmune Diseases; Blood Proteins; Cerebrospinal Fluid Proteins; Concanavalin A; Female; Glycosylation; Haptoglobins; Humans; Molecular Sequence Data; Peptide Fragments; Pregnancy; Reference Values; Schizophrenia

During the later stages of soluble-antigen (sAg)-induced experimental autoimmune uveoretinitis (EAU), an increase in the relative number of CD8+ lymphocytes has been observed at the site of inflammation in the retina. It has been suggested that these late-appearing CD8+ cells might down-regulate this acute disease process. To determine the role of the CD8+ cells in EAU, Lewis rats were depleted of CD8+ cells prior to and during disease and the enucleated eyes examined histologically. The spleen cells from CD8-depleted rats were also examined for their ability to respond to concanavalin A (Con A) and to allogeneic targets as determined by mixed lymphocyte reaction (MLR) and cytotoxicity assays. The results suggest that depleting CD8+ cells had no effect on the course of disease and that CD8+ cells do not play a crucial role in the immunoregulation of EAU.

Topics: Animals; Autoimmune Diseases; CD4-Positive T-Lymphocytes; CD8 Antigens; Concanavalin A; Eye; Female; Immunoenzyme Techniques; Lymphocyte Culture Test, Mixed; Rats; Rats, Inbred Lew; Retinitis; Spleen; T-Lymphocytes; Uveitis

Adjuvant arthritis (AA) and type II collagen (CII)-induced arthritis (CIA) in the rat serve as models of chronic human arthritis. Adoptive transfer of AA was observed in 21 of 25 Lewis rats given concanavalin A (Con A)-treated spleen cells prepared from animals immunized with Mycobacterium butyricum in mineral oil (complete Freund's adjuvant, CFA). No arthritic changes were noted in rats given spleen cells obtained from donors that had received incomplete Freund's adjuvant (IFA, 0/22), type I collagen in IFA (CI-IFA, 0/6) or CII-IFA (0/28). Administration of spleen cells from IFA, CI-IFA or CII-IFA-injected animals did not modify the development of CIA when these rats were subsequently challenged with CII-IFA. However, partial protection against induction of AA was provided by the transfer of spleen cells prepared from rats immunized with CII-IFA (6/11) but not by those obtained from rats injected with IFA (1/15) or CI-IFA (0/3). Rats that did not develop clinically evident arthritis following the administration of spleen cells prepared from CFA-injected rats were also resistant to AA induction by CFA. Pre-treatment of rats with a synthetic peptide, corresponding to amino acids 180-188 of the Mycobacterium 65 kD heat shock protein (65 kD HSP), significantly delayed the onset of AA, but not that of CIA. Disease-specific resistance to AA, provided by spleen cells prepared from rats injected with CII-IFA and by pre-treatment with the 65 kD HSP 180-188 peptide, may result from the induction of protective tolerance to arthritogenic epitopes present in the Mycobacterium and CII preparations.

Topics: Amino Acid Sequence; Animals; Arthritis; Arthritis, Experimental; Autoimmune Diseases; Bacterial Proteins; Chaperonin 60; Chaperonins; Collagen; Concanavalin A; Freund's Adjuvant; Heat-Shock Proteins; Immunotherapy, Adoptive; Lymphocyte Activation; Molecular Sequence Data; Nontuberculous Mycobacteria; Peptide Fragments; Rats; Rats, Inbred Lew; Spleen; T-Lymphocyte Subsets

We previously reported on an altered immune-endocrine feedback loop via the hypothalamo-pituitary-adrenal (HPA) axis in Obese strain (OS) chickens afflicted with spontaneous autoimmune thyroiditis. These animals are deficient in plasma corticosterone increase after antigenic challenge or application of cytokine-containing conditioned medium of mitogen-stimulated spleen cells (CM). To investigate whether the impaired ability to respond to cytokines with glucocorticoid-increasing factor (GIF) activity, e.g. interleukin 1 (IL 1), is restricted to OS chickens as a model for an organ-specific autoimmune disease, we extended our experiments to another autoimmune-prone animal strain, the chickens of the University of California at Davis line 200 (UCD-200). These animals develop an inherited inflammatory fibrotic disease that closely resembles human progressive systemic sclerosis (scleroderma). Application of GIF-containing CM to UCD-200 chickens leads to a transient increase in glucocorticoid serum levels within 1-2 hours comparable to that of controls. But, while corticosterone levels in the latter returned to normal baseline levels after 4 hours, they were still elevated in autoimmune chickens. Although the peak of the glucocorticoid hormone serum concentrations was equal to that of controls, UCD-200 had to secrete twice as much adrenocorticotropic hormone to achieve this corticosterone serum level due to an apparent hyporesponsiveness of the adrenal gland to this secretagogue. The altered cytokine-induced glucocorticoid secretion is found in early as well as in chronic, sclerotic stages of the disease. Cellular alterations in the peripheral blood of UCD-200 chickens during the prolonged elevated corticosterone section, i.e. between 2-4 hours after CM application, are characterized by a significant decrease in the percentage of CD4+ and CD8+ cells. Furthermore, a significant increase in B cells up to 24 hours with a maximum after 1 hour was found. The proliferative response to the mitogen concanavalin A of peripheral mononuclear cells was inversely correlated to the serum corticosterone level, showing a permanent decrease of 80-90% after 1-4 hours in autoimmune animals. This functional alteration in UCD-200 was accompanied by an 80% decrease in serum interleukin 2 (sIL 2) activity 4 hours after CM application. Twenty-four hours later an eight-fold increase in sIL 2 rebound activity was found, indicating that the inhibitory effect of corticosterone in UCD-200 c

Topics: Adrenocorticotropic Hormone; Animals; Autoimmune Diseases; Biological Factors; Cells, Cultured; Chickens; Concanavalin A; Connective Tissue Diseases; Corticosterone; Culture Media, Conditioned; Disease Models, Animal; Feedback; Fibrosis; Immunologic Factors; Interleukin-2; Leukocyte Count; Lymphocyte Activation; Lymphocyte Subsets; Pituitary-Adrenal System; Scleroderma, Systemic; Spleen

Splenic T-cells from lupus strain (NZB/W F1, Mrl/lpr) mice lack the ability to respond to concanavalin A (Con A) by secretion of IL-2 and hence expression of IL-2 receptor and proliferation. These defects were found not only in an aged group (> 5 months) of mice in which obvious clinical 'SLE like' symptoms and elevated levels of serum autoantibodies were observed, but also in mice as young as 4-wk. We demonstrate here that the defective mitogenic activation of T-cells from lupus mice is due to the inability of T-helper cells to produce IL-2 and this defect can be restored by exogenous IL-2 in vitro. Con A-induced cell proliferation and IL-2 receptor expression on CD3+ cells from lupus mice occur only in the presence of exogenous IL-2, whereas normal T-cells from BALB/c and CBA control mice are activated by the mitogen and undergo complete cell cycling in the absence of exogenous IL-2, as they are able to secrete sufficient endogenous IL-2. The detection of impaired T-helper function in young lupus mice, before development of overt disease, and the reversible nature of the defect indicate that defective IL-2 activity may be fundamental to the mechanism of development of pathology in SLE.

Topics: Age Factors; Animals; Autoimmune Diseases; Cells, Cultured; Concanavalin A; Female; Interleukin-2; Lupus Erythematosus, Systemic; Lymphocyte Activation; Mice; Mice, Inbred BALB C; Mice, Inbred CBA; Mice, Inbred NZB; Receptors, Interleukin-2; T-Lymphocyte Subsets; T-Lymphocytes, Helper-Inducer

Patients with hepatitis have multiple immunologic abnormalities, which may be related to cytokine production.. We examined the in vitro production of interleukins (IL-2, IL-4, IL-6), tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma) in purified peripheral blood mononuclear cells (PBMCs) of patients with hepatitis B virus positive (HBV), acute viral hepatitis (A-HBV), HBV + chronic active hepatitis (HBV-CAH), and autoimmune-type chronic active hepatitis (AI-ACH).. IFN-gamma and TNF-alpha production were characteristically higher in patients with A-HBV than in healthy control subjects (p < 0.001). However, patients with AI-CAH produced highly elevated levels of IL-4 and IL-6 compared with patients with A-HBV and HBV-CAH and healthy control subjects. The cytokine profile (PBMC-induced IL-2, IL-4, IL-6, IFN-gamma, and TNF-alpha production) is different in A-HBV, HBV-CAH, and AI-CAH disease. The increased cytokine secretion (IFN-gamma and TNF-alpha in A-HBV and IL-4 and IL-6 in AI-CAH) could reflect altered relative frequencies of different cell phenotypes in these diseases.. Specific cytokine production may be important in the pathophysiology associated with diverse inflammatory states in patients with hepatitis.

Topics: Adult; Autoimmune Diseases; Calcimycin; Concanavalin A; Cytokines; Female; Hepatitis B; Hepatitis, Chronic; Humans; In Vitro Techniques; Interferon-gamma; Interleukin-2; Interleukin-4; Interleukin-6; Leukocytes, Mononuclear; Male; Tetradecanoylphorbol Acetate; Tumor Necrosis Factor-alpha

We have evaluated the effect of human Igs for intravenous use (IVIg) on the onset and development of experimental autoimmune uveoretinitis (EAU), a T cell-dependent autoimmune disease induced in rats by a single immunization with retinal S-antigen (S-Ag). Five consecutive daily infusions of IVIg, starting on the same day as S-Ag immunization, protected (Lewis x Brown-Norway) F1 rats against EAU. The prevention of EAU was IVIg-specific, i.e. mediated by pooled human IgG from multiple donors, since neither infusions of BSA nor infusions of pooled Ig from only two healthy individuals were effective. Treatment with IVIg decreased lymphocyte proliferative and antibody responses to S-Ag and the proliferative response to concanavalin A. Lack of proliferation was not dependent upon generation of suppressor cells. Lymph node (LN) cells from IVIg-treated and S-Ag-immunized animals neither proliferated nor secreted IL-2 in response to S-Ag but proliferated when co-cultured with LN cells from rats immunized with S-Ag. Our findings are compatible with an induction of a state of functional inactivation/anergy of T lymphocytes by infusions of IVIg. This functional inactivation may be due to the presence in IVIg of antibodies that bind both in vivo and in vitro to rat lymphocytes. Results from the present study suggest a novel mechanism by which IVIg may be beneficial in human autoimmune diseases.

Topics: Animals; Antigens; Arrestin; Autoimmune Diseases; Concanavalin A; Eye Proteins; Female; Flow Cytometry; Humans; Immunoglobulins, Intravenous; Interleukin-2; Lymph Nodes; Lymphocyte Activation; Male; Rats; Rats, Inbred BN; Rats, Inbred Lew; Retinitis; Tuberculin; Uveitis

We studied the effects of anti-CD2 monoclonal antibodies (MAb) on spontaneous and induced autoimmune diabetes mellitus in diabetes-prone (DP) and diabetes-resistant (DR) BB/Wor rats. In DP rats, all anti-CD2 MAb prevented spontaneous diabetes and the adoptive transfer of diabetes with Con-A--stimulated acute diabetic spleen cells; OX34 prevented Poly I:C induced accelerated onset of diabetes and the adoptive transfer of diabetes with Con-A--stimulated RT6.1+ T cell depleted DR splenocytes. In DP rats, all anti-CD2 MAb except OX53 depleted CD4+ T cells, without depleting natural killer cells or CD8+ T cells. OX34 injected DR rats were profoundly depleted of CD4+ T cells without evidence of decreased CD8+ T cells, but were not protected against the induction of diabetes by RT6.1+ T-cell depletion and Poly I:C injections. We conclude that anti-CD2 MAbs protect against BB/Wor autoimmune diabetes by depleting CD4+ T cells, preventing the activation of effector cells, or by blocking CD2/ligand interaction between effector and target cells.

Topics: Animals; Antibodies, Monoclonal; Antigens, Differentiation, T-Lymphocyte; Autoimmune Diseases; CD2 Antigens; CD4 Antigens; CD8 Antigens; Concanavalin A; Diabetes Mellitus, Type 1; Flow Cytometry; Hyperinsulinism; Immunotherapy, Adoptive; Injections; Lymph Nodes; Poly I-C; Rats; Rats, Inbred BB; Receptors, Immunologic; Spleen; T-Lymphocytes

We examined T cells isolated from an autoimmune tissue lesion and from lymphoid organs for their ability to secrete tumor necrosis factor-alpha (TNF-alpha) and to adhere to extracellular matrix (ECM) proteins. CD4+ T cells were obtained from spleens, popliteal lymph nodes, and spinal cords of Lewis rats that had been immunized with myelin basic protein (MBP) to induce experimental autoimmune encephalomyelitis (EAE). We now report that, irrespective of whether or not the T cells were activated with MBP or the T cell mitogen concanavalin A (ConA), the T cells isolated from the spinal cord lesions secreted greater amounts of TNF-alpha and adhered better to ECM than did T cells from the draining lymph node. Thus, the lesions of EAE concentrate a subpopulation of CD4+ T cells with enhanced ability to interact with blood vessel wall components and to secrete TNF-alpha.

Topics: Animals; Autoimmune Diseases; Cell Adhesion; Concanavalin A; Encephalomyelitis, Autoimmune, Experimental; Extracellular Matrix; Female; Lymph Nodes; Myelin Basic Protein; Rats; Rats, Inbred Lew; Spinal Cord; Spleen; T-Lymphocytes; Tumor Necrosis Factor-alpha

We examined the effect of gallium (Ga) nitrate on the development of the development of experimental autoimmune encephalomyelitis (EAE). Weekly subcutaneous injections of 10-30 mg/kg prevented clinical signs as well as histopathological changes of EAE. The optimal timing of a single injection of Ga was 6 days after induction of EAE, with amelioration also apparent following a single injection on day 3 or 9 but not day 12. Ga administered in vivo suppressed myelin basic protein (MBP) and purified protein derivative-specific lymphocyte proliferative responses in vitro. Addition of Ga to MBP-specific T lymphocyte line cultures at various times after initiation of culture revealed that Ga exerts an effect at an early stage of cellular activation.

Topics: Animals; Autoimmune Diseases; Cell Division; Cell Line; Concanavalin A; Encephalomyelitis, Autoimmune, Experimental; Gallium; Lymphocyte Activation; Male; Myelin Basic Protein; Rats; Rats, Inbred Lew; T-Lymphocytes; Tuberculin

The generalized lymphoproliferative disease (gld) and lymphoproliferation (lpr) mutations induce the development of strikingly similar autoimmune and lymphoproliferative syndromes in C57BL/6 mice (B6). These syndromes are characterized by hyperglobulinaemia, high levels of circulating autoantibodies and significant splenomegaly and lymphadenopathy resulting principally from the accumulation of a double negative CD4/CD8 T-cell population. These similarities led to the suggestion that the gld and lpr mutations affect two different steps of a common metabolic pathway controlling the differentiation of the T cells. By transferring haematopoietic cells into sublethally irradiated recipients we provide evidence for the different aetiology of the gld- and lpr-induced syndromes. The [gld----gld] chimaeras developed a gld-induced syndrome, like the [lpr----lpr] chimaeras developed a lpr-induced syndrome. However, in contrast to the severe lymphoid aplasia observed in the [lpr----wild] chimaeras, the [gld----wild] chimaeras showed an attenuated form of the gld-induced syndrome. The [lpr----gld] chimaeras developed a lymphoid aplasia (as in the [lpr----wild] chimaeras). This result shows that the gld environment cannot substitute for the lpr environment and allow for the emergence of an lpr-induced pathology.

Topics: Animals; Antibody-Producing Cells; Autoimmune Diseases; Bone Marrow; Concanavalin A; Female; Hematopoietic Stem Cell Transplantation; Lipopolysaccharides; Lymph Nodes; Lymphoproliferative Disorders; Male; Mice; Mice, Inbred C57BL; Mutation; Radiation Chimera; Spleen; Thymus Gland

It has been demonstrated that the single autosomal recessive lpr and gld genes are responsible for the accumulation of unusual T-cell subsets. Although these subsets have been assigned to the T-cell lineage, they share certain antigenic cell surface markers with mature B lymphocytes. Consequently the maturational pathway(s) of these cells has been difficult to fit in the currently accepted models of T-cell differentiation. Previous work has determined that the YE1/19.1 monoclonal antibody (mAb), developed against the EL4 tumour line, reacts with the accumulating T cells in lpr-expressing mice. In this study we report that YE1/19.1 could also be used as a marker for the accumulating T cells in gld-expressing mice and that the hyporesponsiveness seen in gld mice correlated with these accumulating cells. We then demonstrated that the YE1/19.1 antibody also reacts with a subpopulation of neonatal thymocytes as well as a mitogen non-responsive subpopulation of 'double negative' T cells from the spleens and thymuses of non-autoimmune mice. Our findings indicate that the YE1/19.1 mAb will be a useful probe for helping in the eludication of the intra-thymic maturational pathways of T lymphocytes.

Topics: Animals; Antigens, Neoplasm; Autoimmune Diseases; Cell Division; Concanavalin A; Epitopes; Immune Tolerance; Lymphatic Diseases; Lymphoma, T-Cell; Mice; Mice, Inbred C57BL; T-Lymphocyte Subsets; T-Lymphocytes

The three non-allelic gld, lpr and mev mutations in the mouse all lead to profound immunodeficiency besides a splenomegaly and a generalized autoimmunity. Spleen cells from young B6 gld, B6 lpr and B6 mev mice all display a decreased proliferative response to the T-cell mitogen concanavalin A (ConA), but the nature of the deficiency seems very different. No restoration of proliferation could be obtained by adding exogenous recombinant rIL2 to ConA-treated mev spleen cells, this lack of IL2-responsiveness suggesting a lack of (functional) IL2-receptors. In young mice of both gld and lpr strains, a B6 wild-type level of proliferation could be reached by rIl2 addition to ConA-treated spleen cells, this normal responsiveness to exogenous IL2 suggesting a normal expression of IL2-receptors. The endogenous IL2 production by ConA-treated spleen cells decreased very much with ageing in both B6 gld and B6 lpr mice. Yet, IL2 production in young mice revealed an earlier deficiency of the B6 lpr mice: the young B6 gld IL2 levels reached about 60% of age-matched B6 wild cell levels, but the B6 lpr levels reached 14% only. Finally the addition of exogenous rIL2 to ConA-pretreated cells from old B6 gld and B6 lpr mice, while enhancing the proliferative responses, could not restore the B6 wild-type levels. This suggests that, with ageing, the expression of functional IL2-receptors may become as abnormal in these gld and lpr mutants as it is from birth in the mev mutant mice.

Topics: Age Factors; Animals; Autoimmune Diseases; Cells, Cultured; Concanavalin A; Disease Models, Animal; Interleukin-2; Lymphoid Tissue; Mice; Mice, Mutant Strains; Mitosis; Recombinant Proteins; T-Lymphocytes

The authors previously reported that FK506 effectively suppressed the induction of experimental autoimmune uveoretinitis (EAU) in rats with much lower doses than cyclosporine A. This study was aimed at analyzing the immune status of the FK506-treated and EAU-suppressed rats and examining the hypothesis whether the agent could induce antigen-specific suppressor T (Ts) cells. It was found that spleens from S-antigen-immunized and FK506-treated rats contained a population of Ts cells inhibiting the proliferative responses of S-antigen-sensitized lymphocytes to S-antigen, yet these cells did not affect the proliferative responses of interphotoreceptor retinoid-binding protein (IRBP)-sensitized lymphocytes to IRBP. The helper T (Th) cells did not exhibit such suppressor activities. Furthermore, transfer of Ts cells from S-antigen-immunized and FK506-treated rats to naive syngenic rats induced partial inhibition of EAU induction or delay of EAU onset after immunizing the recipient rats with S-antigen. Lymphocytes from the EAU-suppressed recipients showed low proliferative response to S-antigen and low levels of antibody to S-antigen. These data thus indicate that FK506 treatment after S-antigen immunization induces an activation of Ts cells specific to S-antigen and that the Ts cells might contribute, at least in part, to the uniquely prolonged and intensive immunosuppression by FK506.

Topics: Animals; Anti-Bacterial Agents; Antigens; Arrestin; Autoimmune Diseases; Concanavalin A; Epitopes; Eye Proteins; Immunization; Immunosuppressive Agents; Immunotherapy, Adoptive; Lymphocyte Activation; Male; Rats; Rats, Inbred Lew; Retinitis; Retinol-Binding Proteins; Spleen; T-Lymphocytes, Helper-Inducer; T-Lymphocytes, Regulatory; Tacrolimus; Uveitis

Using an in vitro lymphocyte proliferation assay we screened several cyclic peptide antibiotics (bacitracin, oleandomycin, capreomycin, colistin, virginiamycin, and gramicidin S) for their immunosuppressive activity. Gramicidin S (GrS) was found to inhibit [3H]-thymidine incorporation into concanavalin A-stimulated and E coli lipopolysaccharide-stimulated lymphocytes. In vivo studies, experimental autoimmune uveoretinitis (EAU) and pinealitis were induced in female Lewis rats by immunization with bovine S-antigen and experimental autoimmune encephalomyelitis (EAE) were induced by immunization of rats with rat brain homogenates. GrS suppressed the onset of these inflammatory diseases at nontoxic concentrations. Evidence was obtained that GrS inhibits [3H]-thymidine incorporation into lymphocytes by preventing transport of the compound across the membrane. Since GrS binds to various cell membranes, GrS would suppress the proliferation of not only lymphocytes but also of other immune cells by modifying cell membrane properties. The present study indicates that a search for compounds which cause proper cell membrane modification should be a worthwhile strategy for development of immunosuppressive drugs.

Topics: Amino Acid Sequence; Animals; Antigens; Arrestin; Autoimmune Diseases; Concanavalin A; Encephalomyelitis, Autoimmune, Experimental; Eye Proteins; Female; Gramicidin; Immunization; Immunosuppressive Agents; Lipopolysaccharides; Lymphocyte Activation; Lymphocytes; Molecular Sequence Data; Phosphoric Monoester Hydrolases; Pineal Gland; Rats; Rats, Inbred Lew; Retinitis; Spinal Cord; Spleen; Thymidine; Uveitis, Posterior

The predominant T lymphocytes that accumulate in the peripheral lymphoid tissues of mice homozygous for the lpr gene bear the phenotype CD3+CD4-CD8-. By certain functional criteria these cells would appear to have impaired CD3-mediated signal transduction, in that they do not respond to alloantigen and produce little if any detectable IL-2 or other lymphokines. However, the signal pathway appears adequate for achieving other T cell functions, including induction of high affinity IL-2R, and thymic deletion. To clarify the basis of this seeming discrepancy, we examined transmembrane signal transduction in T cell subsets of lpr/lpr (lpr) and +/+ mice, as defined by increased [Ca2+]i and the generation of inositol phosphates (InsPs). Stimulation of lpr CD4-CD8- cells with anti-CD3 antibody produced prompt and sustained increases in the concentration of [C2+]i and in InsPs. Similar responses occurred in mature T cells from lpr and +/+ mice, except for the somewhat slower kinetics of their increased [Ca2+]i. In marked distinction to the anti-CD2-mediated response, Con A, even in high doses, could not stimulate any increase of [Ca2+]i in lpr CD4-CD8- cells, and only modest increases in InsPs. Mature T cells, whether of lpr or +/+ origin, yielded normal increased [Ca2+]i with Con A. The reason for the differences in signal transduction between anti-CD3 and Con A stimulation of lpr CD4-CD8- cells may relate to the absence of surface structures on these immature T cells that are required for activation by Con A but not by anti-CD3. The data demonstrate that the CD3 complex in lpr CD4-CD8- T cells can couple to phospholipase C to hydrolyze phosphoinositides. These activation properties of lpr CD4-CD8- T cells have interesting functional parallels to thymocytes at the time of thymic selection, as well as tolerance induction of mature T lymphocytes.

Topics: Animals; Antibodies, Monoclonal; Antigens, Differentiation, T-Lymphocyte; Autoimmune Diseases; Calcium; CD3 Complex; CD4-Positive T-Lymphocytes; Concanavalin A; Inositol Phosphates; Interleukin-2; Lymphocyte Activation; Mice; Mice, Mutant Strains; Receptors, Antigen, T-Cell; Signal Transduction; T-Lymphocyte Subsets; Tetradecanoylphorbol Acetate; Time Factors; Type C Phospholipases

Effective T cell vaccination against experimental autoimmune diseases involves treatment with activated, autoimmune T lymphocytes. The present study was undertaken to learn whether antigen-specific T cells present in low frequency could be selected in vitro without using the specific antigen. The rat models of adjuvant arthritis and experimental autoimmune encephalomyelitis were investigated using proliferation assays and limiting dilution techniques to quantify the changes in reactivity of a heterogenous population of lymphocytes to the relevant antigen. Stimulation with concanavalin A for 2 d and then culture in IL-2-containing medium led to a substantial increase in the activity and frequency of the specific autoimmune T cells. Enrichment of antigen-specific T cells could be demonstrated using lymph node, spleen, or peripheral blood lymphocytes, from rats late in the course of disease. The effect was not evident in lymphocytes from the thymus. These results are relevant to the clinical application of T cell vaccination and to investigation of self-antigens in autoimmune disease.

Topics: Animals; Arthritis; Arthritis, Experimental; Autoimmune Diseases; Cells, Cultured; Concanavalin A; Female; Interleukin-2; Lymph Nodes; Lymphocyte Activation; Male; Mycobacterium tuberculosis; Rats; Rats, Inbred Lew; T-Lymphocytes; Vaccination

MRL/l mice develop progressive, virulent autoimmune disease that has many of the features of systemic lupus erythematosus. Prophylactic treatment of MRL/l mice with syngeneic photoinactivated autoimmune splenocytes improves survival and inhibits the fulminant hyperproliferation of abnormal T cells and the production of high titer anti-DNA antibody invariably found in untreated mice. The proliferation of Thy 1+ splenic T cells was significantly decreased, and prolonged retention of the response to T-cell mitogen was found in treated mice. Treatment with unmodified cells induced a partial inhibition of disease features which did not prolong survival rates. These results suggest that phototherapy potentiates a normal immunoregulatory process which enables suppression of the development of abnormal cell populations in young MRL/l mice with relatively intact immune systems.

Topics: Animals; Autoantibodies; Autoimmune Diseases; Concanavalin A; DNA; Female; Light; Lipopolysaccharides; Lupus Erythematosus, Systemic; Lymphocyte Activation; Lymphocyte Transfusion; Lymphocytes; Lymphoid Tissue; Mice; Mice, Inbred Strains; Phenotype; Spleen; Survival Analysis; Transplantation, Isogeneic

Topics: Animals; Antibodies, Anti-Idiotypic; Antibodies, Monoclonal; Antibody Formation; Autoimmune Diseases; B-Lymphocytes; CD4 Antigens; Concanavalin A; Humans; Lymphocytes; Male; Middle Aged; Rats; Recombinant Proteins; Tetanus Toxoid; Vasculitis, Leukocytoclastic, Cutaneous

T cell vaccination against experimental autoimmune disease is herein shown to be mediated in part by anti-ergotypic T cells, T cells that recognize and respond to the state of activation of other T cells. The anti-ergotypic response thus combines with the previously shown anti-idiotypic T cell response to regulate autoimmunity.

Topics: Animals; Antigens, Bacterial; Autoimmune Diseases; Concanavalin A; Encephalomyelitis, Autoimmune, Experimental; Hypersensitivity, Delayed; Immunization; Immunization, Passive; Immunoglobulin Idiotypes; Lymphocyte Activation; Mycobacterium tuberculosis; Myelin Basic Protein; Rats; Rats, Inbred Lew; T-Lymphocytes

Quantitative changes of concanavalin A (Con A)-reactive proteins in serum samples obtained from rats with induced inflammation and from patients with inflammatory and autoimmune diseases were examined by use of lectin blots. Treatment of rats with a single dose of fermented yeast to induce inflammation caused an extensive increase in Con A-reactivity. These changes were time dependent and were similar in both sexes of the animals. When we examined serum samples obtained from patients with various inflammatory disorders for their Con A-reactive proteins as compared with normal donors, we noted that the Con A-reactivity increased in patients with rheumatoid arthritis and systemic lupus erythematosus. Among all the glycoproteins examined by lectin blots with use of Con A, a set of five proteins was selected for detailed analysis by densitometric scanning. These included alpha 2-macroglobulin, P-150, P-95, P-40, and P-35, of Mr 180,000, 150,000, 95,000, 40,000, and 35,000, respectively, by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reducing conditions. Densitometric scanning analysis of the lectin blots revealed that the Con A-reactivity of these proteins increased during inflammation. Because alpha 2-macroglobulin is not an acute-phase protein in humans, an increase in Con A staining of this protein suggested that altered glycation is associated with autoimmune diseases. Thus, study of changes in Con A-reactive proteins in human sera may facilitate our understanding of the etiology and pathophysiology of autoimmune diseases.

Topics: alpha-Macroglobulins; Animals; Arthritis, Rheumatoid; Autoimmune Diseases; Blood Proteins; Collodion; Concanavalin A; Electrophoresis, Polyacrylamide Gel; Female; Glycoproteins; Inflammation; Kinetics; Lupus Erythematosus, Systemic; Male; Molecular Weight; Rats; Rats, Inbred Strains

Lymphocytes of autoimmune mice have been reported to have defective IL-2 production and proliferation in response to the mitogen concanavalin A. We have examined transcription of lymphokine genes in Con A stimulated spleen cells from both autoimmune and normal mice and found that IL-2, IL-4 and gamma-interferon (IFN gamma) were induced in all mice tested. Spleen cells were taken from young (pre-disease) or old (clinically active) MRL/lpr (lpr) and male BXSB autoimmune mice and from their normal counterparts (MRL/n, BXSB females, BALB/c and DBA/2) and stimulated with Con A. Con A induced production of IL-2, IL-4 and IFN gamma message and protein, and kinetics of induction did not vary significantly among the strains. However, in old lpr mice, levels of IL-2 protein and mRNA were about 10-fold lower than in other strains; IL-4 protein and mRNA were decreased approximately three-fold; and IFN gamma mRNA was readily detected in unstimulated cells and low but detectable levels of protein were produced constitutively. In contrast, little or no defect in IL-2 or IL-4 transcription or secretion were seen in male BXSB mice and no constitutive IFN gamma transcription was seen in this strain. These data indicate that all three lymphokine genes are activated by Con A in autoimmune mice, even though Con A-induced proliferation is defective in these mice. Furthermore, autoimmune mouse strains vary in terms of lymphokine expression: male BXSB mice display a normal lymphokine profile, whereas lpr mice show a marked imbalance of lymphokines compared to normal controls.

Topics: Animals; Autoimmune Diseases; Cell Division; Concanavalin A; Genes; Interferon-gamma; Interleukin-2; Interleukin-4; Interleukins; Lupus Erythematosus, Systemic; Lymphocytes; Lymphokines; Mice; Mice, Inbred Strains; Spleen; Transcription, Genetic

The immunomodulatory effects of Neurotropin, a substance extracted from inflammatory skin of rabbits inoculated with vaccinia virus, were assessed in autoimmune-prone (NZB/NZW) F1 (B/W F1) mice. The concanavalin A (Con A)-induced proliferative response of spleen cells was markedly decreased in aged B/W F1 mice as compared with young B/W F1 mice. Neurotropin, when administered i.p. to aged B/W F1 mice, significantly increased the Con A-induced proliferative response. In aged B/W F1 mice, interleukin-2 (IL-2) production by Con A-stimulated spleen cells was severely impaired and IL-2 responsiveness of Con A-activated spleen cells was partially decreased in comparison with young B/W F1 mice. Neurotropin, administered to the aged B/W F1 mice, restored IL-2 production by Con A-stimulated spleen cells to the level of young B/W F1 mice. Furthermore, Neurotropin completely restored the IL-2 responsiveness of Con A-activated spleen cells from aged B/W F1 mice. To test whether Neurotropin exerts its immunoregulatory activities in B/W F1 mice by restoring IL-2 production, we directly examined the effect of recombinant IL-2 on the immune functions of spleen cells in vitro. Recombinant IL-2 markedly enhanced Con A-induced proliferative response of aged B/W F1 mice. Furthermore, the suppressive activity of spleen cells which had been activated by Con A in the presence of rIL-2 was significantly increased. These results indicate that some immunoregulatory functions of aged B/W F1 mice can be corrected by IL-2 and suggest that Neurotropin restores immunoregulatory activity in B/W F1 mice by the recovery of IL-2 production.

Topics: Adjuvants, Immunologic; Animals; Antibody Formation; Autoimmune Diseases; Cell Division; Concanavalin A; Female; In Vitro Techniques; Interleukin-2; Lymphocyte Activation; Male; Mice; Mice, Inbred BALB C; Mice, Inbred DBA; Mice, Inbred NZB; Polysaccharides; Spleen; T-Lymphocytes

The presence of the homozygous lpr gene (lpr/lpr) in MRL mice has been regarded as mandatory for the development of the early onset of lupus disease, T-cell dysfunction, and polyclonal B-cell activation. Congeneic MRL mice lacking the lpr gene (MRL +/+) display neither the lupus disease nor the immunological abnormalities within the first year of life. In this study we examined the cellular functions of MRL mice heterozygous at the lpr locus. The results indicate that MRL mice heterozygous at the lpr locus display intermediate delayed-type hypersensitivity compared with homozygous lpr/lpr mice on the one hand and congeneic +/+ mice on the other. Furthermore, proliferative responses to concanavalin A, measured by uptake of [3H]thymidine, were significantly lower in MRL mice heterozygous at the lpr locus than in +/+ mice, but significantly higher than in homozygous MRL lpr/lpr mice. Polyclonal B-cell activation, assessed by measurement of frequencies of IgG-secreting spleen cells, a prominent feature in MRL lpr/lpr mice, was significantly lower in lpr/+ mice and totally absent in +/+ mice. Furthermore, spleen cells spontaneously secreting auto-antibodies were found in large numbers in MRL lpr/lpr mice and in considerably lower but still significant numbers in heterozygous MRL +/lpr mice. In contrast, spleen cells from matched MRL +/+ mice did not display any spontaneous autoantibody production. Taken together, these data provide evidence for immunomodulatory properties of the heterozygous lpr gene.

Topics: Animals; Autoantibodies; Autoimmune Diseases; B-Lymphocytes; Concanavalin A; Female; Gene Expression; Heterozygote; Hypersensitivity, Delayed; Immunoglobulin G; Interleukin-2; Lymphocyte Activation; Lymphoproliferative Disorders; Male; Mice; Mice, Mutant Strains; Spleen; T-Lymphocytes

Concanavalin A-activated T-lymphocyte suppression of IgG production was found to be significantly impaired in patients with untreated active autoimmune chronic hepatitis when compared to normals or patients with inactive disease. When the dose-response effect of TP-1, a calf thymic extract, on in vitro suppressor cell activity was assessed, lymphocytes from six out of eight patients with previously reduced suppressor cell function showed a significant improvement, while over a similar range the suppressor cell activity of most normal controls declined. These results support the possibility that defective immunoregulation in patients with autoimmune chronic active hepatitis may be related to a deficiency in thymic hormone levels.

Topics: Adjuvants, Immunologic; Adult; Aged; Autoimmune Diseases; Concanavalin A; Female; Hepatitis, Chronic; Humans; Immunoglobulin G; In Vitro Techniques; Male; Middle Aged; T-Lymphocytes, Regulatory; Thymus Extracts

BB rats are prone to develop an autoimmune form of insulin-dependent diabetes mellitus (IDDM) and thyroiditis. Development of autoimmunity is thymus dependent. Previous studies have shown that BB rats lack a population of T cells bearing the RT6 antigen and have very low numbers of suppressor/cytotoxic T cells. In this study, we confirm that BB rats have decreased numbers of phenotypic T suppressor/cytotoxic (Ts/c) cells (OX19+, OX8+ cells) in their lymphoid organs. Moreover, we find that the phenotypic Ts/c cells of BB rats lack apparent cytotoxic activity. These T cells fail to kill allogeneic target cells in a cell-mediated lympholysis assay and fail to generate lectin-dependent cytotoxicity. The addition of interleukin 2, gamma-interferon, and other lymphokines to cultures of BB T cells does not induce functional cytotoxic T lymphocytes. We find that the activated T cells of newly diabetic rats are incapable of killing major-histocompatibility-complex-matched islet cells, despite the ability of these cells to cause IDDM in passive transfer experiments. We conclude that autoimmune disease occurs in BB rats in the absence of functional cytotoxic T cells.

Topics: Animals; Antigens, Differentiation, T-Lymphocyte; Autoimmune Diseases; Concanavalin A; Diabetes Mellitus, Type 1; Hypersensitivity, Delayed; Interferon-gamma; Interleukin-2; Islets of Langerhans; Lymphocyte Activation; Lymphoid Tissue; Rats; Rats, Mutant Strains; T-Lymphocytes, Cytotoxic

A possible role for retinal pigment epithelial cells (RPE) as local antigen presenting cells in immune inflammatory eye disease was investigated by studying the in vitro response of human RPE cells to stimulation with purified IFN-gamma or Con A induced lymphokine. RPE cells cultured with a single dose of 50-1000 u/ml IFN-gamma for up to 8 days to allow maximal Class II gene transcription, expressed HLA DP, DR and DQ antigens in a dose-dependent manner with 80% or more of cells positive for each antigen at the higher concentration. After removal of a suboptimal IFN-gamma stimulus, HLA-DR antigen expression persisted for at least 15 days. HLA-DP and DQ antigens persisted only after maximal IFN-gamma stimulation. Lymphokine from Con A stimulated lymphocytes induced higher levels of DR and DQ expression (80%) over DP (15%) implying complex interactions with other mediators present in the lymphocyte culture supernatant. Since RPE cells phagocytose and recycle autoantigen-rich retinal rod outer segments and co-express HLA DR and DQ Class II antigens in response to IFN-gamma stimulation, an immunoregulatory role in conditions in which retinal autoimmunity is implicated, such as chronic idiopathic posterior uveitis and retinal vasculitis is postulated for these cells.

Topics: Autoimmune Diseases; Cells, Cultured; Concanavalin A; HLA-DP Antigens; HLA-DQ Antigens; HLA-DR Antigens; Humans; Interferon-gamma; Kinetics; Lymphokines; Pigment Epithelium of Eye; Uveitis

Cytotoxic treatment of BALB/c cells from different peripheral lymphoid tissues by a cocktail of monoclonal antibodies against Thy-1, Ly-1, L3T4 and Ly-2 differentiation markers (anti-T cocktail) plus complement eliminates all mature T lymphocytes. Yet a population of dull Thy-1+, Ly-1-, L3T4-, Ly-2-, corresponding to about 1% of the initial population, can be detected by flow cytometry which proliferate under concanavalin A stimulation. These anti-T killing-resistant cells (TKR) were previously shown to be capable of differentiating in culture into class II-restricted autoreactive T helper cells. We demonstrate here that such cells can be detected in mice of BALB/c and DBA/2 genetic background but are absent in C57BL/6 and B10 animals. The presence of TKR cells is dominant in (BALB/c x C57BL/6)F1 hybrids and genetically controlled by two genes which are neither H-2 nor Igh linked. TKR cells are also detected in young NZB mice but disappear with the development of the systemic autoimmune disease in old animals. Thy-1+, L3T4-, Ly-2- cells from MRL lpr/lpr mice also respond to concanavalin A but are removed by the anti-T treatment. Altogether, arguments are presented suggesting that TKR cells represent a particular subset of double-negative peripheral T cells which may correspond to autoreactive T cell recursors that would escape the thymic selection. We postulate that these cells are present in all mouse strains but their susceptibility to killing by anti-Thy-1 antibodies differs depending on background genes.

Topics: Animals; Antigens, Differentiation, T-Lymphocyte; Antigens, Ly; Autoimmune Diseases; Concanavalin A; Female; Hematopoietic Stem Cells; Lymphocyte Activation; Lymphoid Tissue; Male; Mice; Mice, Inbred Strains; T-Lymphocytes

In autoimmune diseases, mitogen-induced IL-2 production in vitro is generally considered to be diminished despite evidence of lymphoid hyperactivity in vivo. HgCl2 is known to cause T-dependent polyclonal B cell activation in Brown-Norway (BN) rats, resulting in autoimmune disease. We show here that the IL-2 producing capacity of cells from HgCl2-treated BN rats is low, but that HgCl2 treatment in vitro (10(-7) M) enhances IL-2 production of normal BN splenocytes. Lewis (LEW) rats are resistant to HgCl2-induced autoimmune disease. HgCl2 treatment of these rats in vivo does not significantly decrease the IL-2 production of their splenocytes. However, HgCl2 treatment of normal LEW splenocytes in vitro enhances their IL-2 production but this requires an HgCl2 concentration ten times greater (10(-6) M) in LEW than in BN rats. These findings are discussed in an attempt to resolve the paradox between the in vivo immune hyperactivity seen in HgCl2-treated BN rats, and the apparently low IL-2 production of their splenocytes in vitro.

Topics: Animals; Autoimmune Diseases; Cell Division; Cells, Cultured; Concanavalin A; Interleukin-2; Kinetics; Lymphocyte Activation; Lymphocytes; Male; Mercuric Chloride; Rats; Rats, Inbred BN; Rats, Inbred Lew; Spleen

In autoimmune chronic active hepatitis (aCAH), autoaggression is believed to derive from a defect in immunoregulation. Antigen non-specific Concanavalin A (Con A) induced suppressor cell function has been reported to be impaired. In 11 children with aCAH we have investigated inhibition of production of a specific antibody (anti-tetanus toxoid, anti-TT) by suppressor cells induced either by a non-specific stimulus (Con A) or by the specific antigen (tetanus toxoid, TT). Con A induced suppression of anti-TT was significantly lower in patients (15.7 +/- 2.5%) than in controls (46.7 +/- 4.4%; P less than 0.01). In contrast, high dose tetanus toxoid induced suppression was similar in patients and controls (69.8 +/- 4.2, 72.0 +/- 3.6%, respectively). Both groups had similar serum anti-TT levels and in vitro production of anti-TT in response to optimal dose of TT. Our data indicate that antibody production to a T cell-dependent antigen is under the control of at least two regulatory mechanisms, one antigen specific and one antigen non-specific, only the latter being defective in aCAH.

Topics: Adolescent; Antibodies, Bacterial; Autoimmune Diseases; Child; Concanavalin A; Epitopes; Female; Hepatitis, Chronic; Humans; Male; T-Lymphocytes, Regulatory; Tetanus Toxoid

BXSB male mice serve as one of several murine models of human systemic lupus erythematosus. T-cell abnormalities in these mice involve decreased production of and responsiveness interleukin 2 (IL-2) and are age-related. The studies presented here investigated the mechanism of these T-cell defects. The results suggest that excessive suppressor-T-cell activity as well as soluble inhibitors of IL-2 production and activity, including PGE, are not responsible for the low levels of IL-2 observed in culture supernatants of Con A-stimulated lymphocytes from "old" (3-6 months) BXSB male mice. Supplementation of Con A-stimulated lymphocyte cultures from BXSB male mice with human IL-1 or normal murine accessory cells did not augment IL-2 production. Reduced proliferative responses were observed in bulk cultures of Con A- or alloantigen-stimulated "old" BXSB male lymphocytes, which were not enhanced by exogenous IL-2. Limiting dilution analysis revealed reduced frequencies of Con A- and alloantigen-inducible IL-2-reactive T cells in these mice. These results suggest intrinsic defects in the ability of T cells from "old" BXSB male mice to be activated to produce and respond to IL-2.

Topics: Age Factors; Animals; Antigen-Presenting Cells; Autoimmune Diseases; Cell Differentiation; Concanavalin A; Female; Indomethacin; Interleukin-1; Interleukin-2; Isoantigens; Kinetics; Lymph Nodes; Lymphocyte Activation; Lymphocytes; Male; Mice; Mice, Mutant Strains; Prostaglandins E; Spleen; T-Lymphocytes, Regulatory

Lymph node T cells from autoimmune MRL/Mp-lpr/lpr mice, but not from congeneic MRL/Mp-+/+ mice, spontaneously proliferate and produce IL 2 when cultured in vitro for 5 to 7 days. This autologous activation depends critically on the length of in vitro culture and the initial culture density, indicating that cell to cell interaction may be essential. Phenotypic characterization of cultured cells suggests that both L3T4+ and Lyt-2+ T cells proliferate. However, only L3T4+ T cells produce IL 2. Mixing experiments reveal that the inability of freshly isolated lymph node cells from MRL/Mp-lpr/lpr mice to proliferate is not due to the presence of suppressor cells. Supernatant from 7-day cultures failed to induce freshly isolated cells to proliferate. Thus, the failure of freshly isolated cells to spontaneously proliferate and secrete IL 2 is not due to the inability of the cells to produce soluble mediators. Similar to the inactivation of normal T lymphocytes, in vitro addition of monoclonal anti-L3T4 or anti-IL 2 receptor antibody significantly inhibits the activation of these cultured lymphocytes. Spontaneous proliferation and IL 2 production can be blocked by the addition of monoclonal anti-I-Ak but not by monoclonal anti-I-Ad. Spontaneous proliferation and IL 2 production can be detected in young (4-wk-old) MRL/Mp-lpr/lpr mice at a time when their lymphocyte composition and physiology appear to be normal. More interestingly, spontaneous proliferation and IL 2 production cannot be detected in C57BL/6J mice bearing the lpr/lpr gene. These experiments support the notion that aberrant syngeneic autoreactivity may act as an accelerating factor in the pathogenesis of lymphoproliferation and autoimmunity in MRL/Mp-lpr/lpr mice.

Topics: Animals; Antibodies, Monoclonal; Antigens, Differentiation, T-Lymphocyte; Antigens, Surface; Autoimmune Diseases; Cells, Cultured; Concanavalin A; Contact Inhibition; Interleukin-2; Lymph Nodes; Lymphocyte Activation; Lymphoproliferative Disorders; Mice; Mice, Inbred Strains; Mice, Mutant Strains; Phenotype; Receptors, Immunologic; Receptors, Interleukin-2; T-Lymphocytes

Topics: Aging; Animals; Autoimmune Diseases; Calcimycin; Concanavalin A; DNA; Gene Expression Regulation; Interleukin-2; Lymphocyte Activation; Male; Mice; Proto-Oncogenes; Receptors, Immunologic; Receptors, Interleukin-2; Tetradecanoylphorbol Acetate

Intravenous transfusion of concanavalin A-activated splenic cells from acutely diabetic BB or diabetic BB/hooded hybrid donor rats into 6- to 36-h-old neonate recipients of diabetes-prone and -resistant rat lines induced insulitis and in some severe diabetes. These effects were observed 10-20 days after the injection of the blasts. Focal lesions of insulitis were absent in neonates killed 1 and 3 days after the blast injection but were observed in neonates killed on the 5th and 8th day. As determined by autoradiography after the injection of [3H]thymidine-labeled blasts, numerous blast cells migrated and settled in various immature lymph nodes and in the spleen within 24 h after injection. Focal mononuclear infiltrations in the islets containing labeled and unlabeled cells were again observed on the 5th and 8th day but not on the 1st and 3rd day after injection. These experiments indicate that target-specific blasts undergo a short phase of proliferation and maturation in lymphoid organs of the recipients, before initiating the autoimmune process in the pancreatic islets. They further suggest that specific immune cells rather than humoral anti-islet antibodies are more likely to play the major role in this autoimmune animal model of diabetes.

Topics: Animals; Animals, Newborn; Autoimmune Diseases; Cells, Cultured; Concanavalin A; Diabetes Mellitus, Experimental; Inflammation; Islets of Langerhans; Rats; Rats, Inbred BB; Spleen

The effect of age on the ability to elicit the various immune functions comprising experimental autoimmune thyroiditis in mice has been examined. Compared with young mice (2 to 3 mo), CBA/CaJ and A/J aged mice (20 to 30 mo) show a drastic reduction in their ability to develop circulating antibody after injection of mouse thyroglobulin (MTg) or mouse thyroid extract (MTE) in complete Freund's adjuvant (CFA). Delayed-type hypersensitivity responses were also depressed, as well as the ability of aged lymph node cells to proliferate in vitro to antigen and the ability of aged splenic T cells to function as helper cells for in vitro antibody production. However, after injection of these thyroid antigens in CFA, aged mice developed thyroid lesions either comparable to or only slightly less intense than those observed in young mice. The disparity between the levels of immune responses and thyroid lesions observed in aged mice can be explained by the greater susceptibility of aged thyroids to tissue damage, since transfer of identical numbers of Con A-activated MTE-primed young splenocytes to young and aged recipients results in a more severe thyroiditis in the aged recipients. Priming mice to MTE in CFA at 9 mo of age, at which time mice are responsive to MTE, did not enhance either T or B cell responsiveness to injection of MTE in CFA at 24 mo of age. Lymphocytes from MTE-injected aged mice also failed to transfer thyroiditis to young recipients after in vitro activation of the lymphocytes with Con A.

Topics: Aging; Animals; Autoantibodies; Autoimmune Diseases; Concanavalin A; Female; Lymphocyte Activation; Mice; Mice, Inbred A; Mice, Inbred CBA; Spleen; T-Lymphocytes; Thyroglobulin; Thyroiditis

The essential requirement for adoptive transfer of autoimmune diseases such as experimental allergic encephalomyelitis (EAE) by T lymphoblasts from established T cell lines, is a prior activation of these cells by autoantigen or mitogen. We have investigated the possibility of modulating this activation process by using monoclonal antibodies directed against rat leukocyte differentiation antigens. We report here that antigen-driven activation of autoimmune, encephalitogenic T cells from established myelin basic protein (MBP)-specific rat T cell lines can be inhibited by some, but not all, antibodies against RT1.B Class II restriction elements. In addition, monoclonal antibodies with specificity for rat leukocyte common antigen (OX-1) and T cell differentiation antigens W3/13 and W3/25 are inhibitory, while monoclonal antibody OX-8 with specificity for T cytotoxic/suppressor cells has no effect. We also observed that concanavalin A-induced activation of the T cells is more resistant to the inhibitory effect of monoclonal antibodies, and can be blocked effectively only by antibody OX-1. This demonstration that autoimmune T cell function can be inhibited by monoclonal antibodies points the way in suggesting cellular targets for immunotherapeutic purposes.

Topics: Animals; Antibodies, Monoclonal; Autoantibodies; Autoimmune Diseases; Cell Line; Concanavalin A; Guinea Pigs; Humans; Interleukin-2; Lymphocyte Activation; Mice; Myelin Basic Protein; Rats; Rats, Inbred Lew; T-Lymphocytes

Con A-induced suppressor cells were studied in 20 patients with autoimmune thrombocytopenic purpura and 20 normal controls. Percentage of suppression was determined on autologous and allogenic lymphocytes during blast transformation with phytohemagglutinin (PHA). In 10 patients and 10 controls helper (T4) and suppressor (T8) subsets were also determined, using monoclonal antibodies. We found a significant decrease in patients' suppressor cell activity both with autologous and allogeneic lymphocytes. Patients' responder lymphocytes were also impaired when tested with normal suppressor cells. The numbers of T4 and T8 in patients was found to be normal although the ratio T4/T8 was somewhat lower than in normal controls. There was a significant direct correlation between the numbers of T4 of patients and their suppressor cell activity on allogeneic lymphocytes suggesting an immunoregulatory defect at the level of induction of suppressor cells.

Topics: Adolescent; Adult; Aged; Autoimmune Diseases; Child; Child, Preschool; Concanavalin A; Humans; Immune System Diseases; Lymphocyte Activation; Lymphocyte Culture Test, Mixed; Middle Aged; Phytohemagglutinins; Purpura, Thrombocytopenic; T-Lymphocytes, Helper-Inducer; T-Lymphocytes, Regulatory

We examined the expression of HLA-DR antigen induced by mitogen, mitogen-free supernatants from mitogen-stimulated peripheral blood mononuclear cells (PBMC), or autologous and allogeneic PBMC on thyrocytes cultured for 1-2 weeks (precultured) before the addition of the stimulant. Leucoagglutinin (LAG) and concanavalin A, but not lipopolysaccharide induced HLA-DR expression on thyrocytes from normal subjects (NC) and patients with Graves' disease (GD) and Hashimoto's thyroiditis (HT). The degree of DR expression induced by LAG was significantly less in GD than in NC thyrocytes. This response was dependent on contaminating T cells, especially suppressor-cytotoxic T (Ts/c) cells, NK cells, and HLA-DR+ cells, but not helper-inducer T (Th/i) cells or B cells, in the thyrocyte cultures. OKT3 monoclonal antibody, which activates T cells specifically in the presence of monocytes, also induced thyrocyte HLA-DR expression. Furthermore, interferon-gamma (IFN-gamma) was detected in culture supernatants from LAG-stimulated thyrocytes. Anti-IFN-gamma monoclonal antibody eliminated the ability of LAG to induce HLA-DR. Mitogen-free supernatants from mitogen-stimulated PBMC also induced thyrocyte HLA-DR expression, which was inhibited by anti-IFN-gamma. The supernatants of concanavalin A- or LAG-stimulated PBMC from either untreated or recently treated patients with GD or hypothyroid HT induced less thyrocyte DR expression than NC PBMC. Indeed, the levels of IFN-gamma in supernatants from such patients were lower than those in NC, and the correlation between DR expression and IFN-gamma levels was significant. This IFN-gamma production by PBMC required Th/i cells, NK cells, and HLA-DR+ cells. Before the addition of autologous or allogeneic PBMC, only precultured HT thyrocytes expressed HLA-DR, whereas GD and NC thyrocytes did not. The induction or enhancement of DR expression on autologous thyrocytes by direct coculture with PBMC occurred within 8 days in GD and HT, but not in NC. There was a significant correlation between the serum titer of antithyroid microsomal antibodies and the degree of DR expression. Allogeneic normal PBMC also induced DR expression on NC and GD thyrocytes within 8 days, the effect on the latter being more pronounced than with autologous GD PBMC. Thyrocyte HLA-DR expression induced by autologous GD PBMC and allogeneic normal PBMC required monocytes. Th/i, and NK cells and was blocked by anti-IFN-gamma. However, the enhancement of thyrocyte DR expre

Topics: Adult; Aged; Agglutinins; Antibodies, Monoclonal; Autoimmune Diseases; Cells, Cultured; Concanavalin A; Fluorescent Antibody Technique; Histocompatibility Antigens Class II; HLA-DR Antigens; Humans; Interferon-gamma; Leukocytes; Lipopolysaccharides; Middle Aged; Proteins; T-Lymphocytes; Thyroid Diseases; Thyroid Gland

MRL-lpr mice and their congenic counterparts MRL-+ spontaneously develop an autoimmune disease that resembles systemic lupus erythematosus in humans. The two strains, although congenic, differ by a considerable number of disease parameters, reflecting the expression of the lpr autosomal recessive gene. One paradox that has developed out of the work utilizing the congenic mice is that the gene responsible for lymphoproliferation also appears to be responsible for the inability of T cells to respond to proliferative signals in vitro. In this paper we investigated a possible lpr gene-encoded macrophage defect in these mice. It was found, however, that both the MRL-+ and MRL-lpr mice failed to divide in response to Con A, the lack of division correlating with an inability to secrete the growth promoter interleukin-2. In MRL-+ mice and young MRL-lpr mice this non-responsiveness was corrected by the addition of normal CBA PEC. The defect could not be explained by a failure of MRL-+ or MRL-lpr peritoneal exudate cells to quantitatively or qualitatively provide a source of interleukin-1 to Con A-activated T cells or by the possibility that the peritoneal exudate cells were blocked in their function by the presence of sera-derived autoantibodies and/or immune complexes on their membranes. We postulate that the inability of T cells to proliferate in MRL congenic mice can be explained by two defects: the failure of antigen-presenting cells in MRL-+ and MRL-lpr to provide the necessary signals to immunocompetent T cells, this defect not being associated with the lpr gene, and the lpr gene controlled outgrowth of a unique T-cell population that cannot respond in our assay system.

Topics: Animals; Autoimmune Diseases; Cells, Cultured; Concanavalin A; Genes, MHC Class II; Interleukin-1; Lymphocyte Activation; Macrophages; Mice; Mice, Inbred Strains; Mitosis; T-Lymphocytes

Daunomycin, when conjugated with a targeting antigen by an acid-sensitive spacer, remains inactive at the intravascular pH of 7 but becomes active after cleavage within the acidic lysosomal environment of the target cell. This observation made it possible to construct cytocidal compounds that caused antigen-specific suppression of murine lymphocyte function. When daunomycin was coupled to the hapten conjugate of ovalbumin by an acid-sensitive cis-aconityl group, it caused hapten-specific impairment of immunocompetence in murine B lymphocytes in vitro and in vivo. Furthermore, the response by T lymphocytes to concanavalin A in vitro was selectively eliminated by a conjugate between daunomycin plus the acid-sensitive spacer and a monoclonal antibody specific for T cells.

Topics: Animals; Autoimmune Diseases; Concanavalin A; Daunorubicin; Fluorescein; Fluoresceins; Immunosuppression Therapy; Immunosuppressive Agents; Lymphocyte Activation; Mice; Mice, Inbred CBA; Nitrohydroxyiodophenylacetate; Ovalbumin; Picrates; Spleen; T-Lymphocytes

MRL-+ and MRL-lpr congenic mice differ by the presence and expression of the homozygous recessive lymphoproliferation (lpr) gene. One manifestation of this gene is a massive T cell proliferation that results in a generalized lymphadenopathy in older animals. Interleukin 3 (IL 3), a recently described lymphokine, has been shown to influence lymphocyte differentiation. It was possible that abberrant IL 3 production was the mechanism responsible for the lpr controlled lymphadenopathy. Consequently, in this paper we tested the MRL congenic mice for their ability to produce IL 3. We report that the T lymphocytes from MRL-+ and MRL-lpr could neither respond to pokeweed mitogen in the induction of proliferation nor produce IL 3. Moreover, IL 3 was not produced constitutively nor could be induced at any time period up to 5 days in vitro. This hyporesponsiveness was shown to be controlled at the accessory cell level. Addition of T cell-depleted peritoneal exudate cells from normal major histocompatibility complex (MHC) compatible mice was able to restore the ability to secrete IL 3 in response to pokeweed mitogen in MRL-+ and young MRL-lpr mice. The defect in the accessory cells could be overridden by two means: the incorporation of phorbol myristate acetate in the induction system and preincubation of the cells in tissue culture.

Topics: Animals; Antigen-Presenting Cells; Autoimmune Diseases; Cell Differentiation; Concanavalin A; Interleukin-3; Kinetics; Lymphocyte Activation; Mice; Mice, Mutant Strains; Pokeweed Mitogens; T-Lymphocytes

Diabetes in the BB/W rat is autoimmune in origin, and lymphocytes from acutely diabetic animals activated by concanavalin A (con A) induce the disease in adoptive recipients. We report that irradiation of these cells prevents adoptive transfer of diabetes. Through 60 days of age, diabetes occurred in none of 47 BB/W rats given irradiated con A cells, but in 21 of 36 (58%) given nonirradiated cells. Between 60 and 130 days of age, however, spontaneous diabetes occurred in 18 of 34 untreated control rats (53%) and 16 of 32 rats (50%) given two injections of irradiated con A activated spleen cells. We conclude that irradiation prevents adoptive transfer of BB/W rat diabetes and that irradiated con A activated lymphocytes from acutely diabetic rats do not protect against spontaneous disease in susceptible recipients.

Topics: Animals; Autoimmune Diseases; Cell Survival; Concanavalin A; Diabetes Mellitus, Experimental; Immunization, Passive; Lymphocyte Activation; Lymphocytes; Rats; Rats, Inbred BB; Spleen

Abnormal T-cell regulation of lymphocyte proliferation may contribute towards tissue damaging mechanisms in chronic liver disease. We therefore studied Concanavalin A induced suppressor cell activity in T-T interaction in 47 patients with chronic liver disease, using both an autologous and an allogeneic system. In the autologous system, no differences were found between those with auto-immune chronic active hepatitis, HBsAg positive chronic active hepatitis, primary biliary cirrhosis, alcoholic liver disease and normal controls. However, several abnormalities were identified in allogeneic cultures with normal lymphocytes which allowed separate analysis of the influence of suppressor and responder cells from patients with chronic liver disease. An abnormality of the suppressor population was found in those with autoimmune chronic active hepatitis, primary biliary cirrhosis and alcoholic liver disease, while the responder population was abnormal in those with autoimmune or HBsAg positive CAH. Failure to demonstrate an abnormality in an autologous system may reflect a combined defect of suppressor and responder populations, and in this study the allogeneic system was a more sensitive index of abnormal cellular T-T interaction.

Topics: Autoimmune Diseases; Chronic Disease; Concanavalin A; Hepatitis B Surface Antigens; Humans; Liver Diseases; Lymphocyte Activation; T-Lymphocytes, Regulatory

Topics: Autoimmune Diseases; Concanavalin A; Humans; Killer Cells, Natural; T-Lymphocytes, Regulatory; Thyroiditis, Autoimmune

The proliferation of peripheral blood lymphocytes, cultured with Con A, can be inhibited by ionizing radiation. Lymphocytes from patients with conditions associated with autoimmunity, such as rheumatoid arthritis, systemic lupus erythematosus and polymyositis, are more radiosensitive than those from healthy volunteers or patients with conditions not associated with autoimmunity. The nuclear material isolated from the lymphocytes of patients with autoimmune diseases is, on average, lighter in density than the nuclear material from most healthy controls. This difference in density is not related to increased sensitivity to ionizing radiation but the degree of post-irradiation change in density (lightening) is proportional to the initial density, i.e. more dense nuclear material always shows a greater upward shift after radiation. The recovery of preirradiation density of nuclear material, 1 h after radiation exposure, taken as an indication of DNA repair, correlates with the radiosensitivity of lymphocyte proliferation (Con A response); failure to return to pre-irradiation density being associated with increased sensitivity of proliferative response. These results require extension but, taken with previously reported studies of the effects of DNA methylating agents, support the idea that DNA damage and its defective repair could be important in the aetio-pathogenesis of autoimmune disease.

Topics: Adult; Aged; Arthritis, Rheumatoid; Autoimmune Diseases; Cell Division; Cell Nucleus; Concanavalin A; DNA; DNA Repair; Humans; Lupus Erythematosus, Systemic; Lymphocytes; Middle Aged; Myositis; Radiation Tolerance

Induction of autoimmune thyroiditis in normal syngeneic CBA/J mice was achieved by injection of 72-hr concanavalin A (Con A)-induced lymphoblasts from donor mice which had been immunized with mouse thyroglobulin (MTg) emulsified with complete Freund's adjuvant (CFA). Injection of lymph node or spleen cells, or frequent injection of serum taken from mice with autoimmune thyroiditis failed to transfer appreciable thyroiditis to recipient mice. Selection by treatment of incubated cells with monoclonal antibody and complement revealed that effector cells in Con A-induced lymphoblast populations for the transfer of autoimmune thyroiditis were Thy-1.2+, Lyt-1.1+, and Lyt-2.1- lymphocytes. These results demonstrate that experimental autoimmune thyroiditis can be adoptively transferred into naive mice by activated Thy-1+, Lyt-2- lymphoblasts.

Topics: Animals; Autoimmune Diseases; Concanavalin A; Female; Immunization, Passive; Lymphocyte Activation; Mice; Mice, Inbred CBA; T-Lymphocytes; Thyroglobulin; Thyroiditis

Anti-histone antibodies (AHA) are spontaneously produced in NZB/NZW mice as part of their autoimmune disease. IgM AHA are usually not detected until after 4 mo of age, and older female mice switch to the production of IgG AHA. We studied the in vitro production of AHA by spleen cells from young (less than or equal to 12-wk-old) NZB/NZW mice. Despite the absence of elevated serum AHA activity, spleen cells from these mice demonstrated marked spontaneous autoantibody production in culture. In kinetic studies, little in vitro production was detectable after 1 day of culture, and maximal accumulation occurred on day 5. Elevated AHA production was apparent by cells from 2-wk-old NZB/NZW mice, and an age-dependent increase in autoantibody production was also noted. Only AHA of the IgM class were detected in cultures of young spleen cells. The in vitro production of IgM AHA in culture was T cell dependent, depletion of T cells resulting in a 70 to 90% reduction in production, which was corrected by the readdition of T cells. In cultures where both IgM AHA and total IgM secretion were measured, a much greater T cell dependence for AHA production was apparent. The requirement for T cells could also be partially replaced by factors present in concanavalin A supernatant. AHA secretion was induced by lipopolysaccharide by using cells from both NZB/NZW and non-autoimmune mice. Although production was greater with NZB/NZW cells, the difference was much less than that for spontaneous production. Thus, AHA-secreting cells that are dependent on in vitro T cell help are present in young NZB/NZW mice. These studies may help define the mechanisms responsible for selective autoantibody secretion in lupus-like disease.

Topics: Aging; Animals; Antibodies, Antinuclear; Autoimmune Diseases; Concanavalin A; Female; Histones; Immunoglobulin M; Lipopolysaccharides; Lymphocytes; Lymphokines; Mice; Mice, Inbred NZB; Spleen; T-Lymphocytes

The mitogenic response to Con A and the production of T cell growth factor or interleukin 2 (IL 2) by splenic and peripheral blood lymphocytes of obese strain (OS) chickens with spontaneous autoimmune thyroiditis have been investigated. By using an optimized method with Con A-coated chicken erythrocytes (MRC), lymphocytes of OS chickens were found to exhibit significantly elevated mitogenic responses as compared with cells from either Normal White Leghorn chickens (NWL) or animals of the Cornell C-Strain (CS), from which the OS has originally been developed. This difference was observed throughout ontogeny up to 15 mo of age, and was associated with increased levels of IL 2 activity in the culture supernatants. The elevated responsiveness of OS T lymphocytes was also found to be manifested in the expression of receptors for IL 2, because Con A-stimulated lymphocytes of OS birds were significantly more effective than those from normal controls in absorbing IL 2 activity from conditioned media (CM) of stimulated spleen cells. High concentrations of CM were suppressive in IL 2 assays, signaling the presence of an inhibitory factor(s) in addition to IL 2. An additional indication for defective immunoregulation was that CM from OS lymphocyte cultures showed significantly less of this suppressive activity in comparison with CM of normal (NWL and CS) lymphocyte cultures. Finally, the spontaneous uptake of 125IUdR of embryonic and early post hatching OS spleen lymphocytes was consistently and significantly enhanced. This difference, however, in contrast to the one observed in Con A responses, was found to decrease with age. The data are discussed in view of the contradictory results concerning T cell functions reported for several autoimmune states in mammals.

Topics: Aging; Animals; Autoimmune Diseases; Chick Embryo; Chickens; Concanavalin A; Erythrocytes; Female; Interleukin-2; Lymphocyte Activation; Lymphokines; Male; Receptors, Immunologic; Receptors, Interleukin-2; Spleen; Suppressor Factors, Immunologic; T-Lymphocytes; Thyroiditis

Injections of media conditioned by concanavalin A-activated spleen cells from acutely diabetic rats accelerated the appearance of diabetes in young Bio-Breeding/Worcester (BB/W) rats. Activity was also found in media conditioned by spleen cells from nondiabetic, W-line Wistar Furth and Buffalo rats. Unconditioned media containing mitogen had no activity. Conditioned media also induced diabetes in resistant W-line BB/W rats but not in Wistar Furth rats. A soluble factor may activate a BB lymphocyte population that promotes diabetes.

Topics: Age Factors; Animals; Autoimmune Diseases; Concanavalin A; Culture Media; Diabetes Mellitus, Type 1; Disease Susceptibility; Female; Immunization, Passive; Lymphocyte Transfusion; Male; Rats; Rats, Inbred BB; Rats, Inbred BUF; Rats, Inbred Strains; Rats, Inbred WF; Spleen

Suppressor T cell function induced by concanavalin A (con A) was evaluated in patients with Graves' disease and Hashimoto's thyroiditis. Patients with Graves' disease were divided into the following two groups: (1) untreated, and (2) euthyroid during antithyroid drug (methylmercaptoimidazole) therapy. T cells (2 X 10(5)), activated by con A for 48 hours, were added to preincubated responder cells (2 X 10(5)) and re-incubated for 7 days in the presence of pokeweed mitogen (PWM). IgG produced in the culture medium was measured by radioimmunoassay and then % suppressions (IgG) were calculated. Thyroid stimulating activity (TSA) in serum was measured by McKenzie's method by means of normal human thyroid slices, and % suppressions (c-AMP) were calculated. IgG produced in lymphocyte culture medium was suppressed by added con A-activated cells in untreated and euthyroid groups of Graves' disease, Hashimoto's thyroiditis and normal controls. The value of % suppression (IgG) was reduced in each group of Graves' disease compared to normal controls. No significant relation was observed between TSA in serum and % suppression (IgG), but three cases with high serum TSA showed low % suppressions (IgG). In 12 cases of Graves' disease, % suppression (IgG) had a positive relation with % suppression (c-AMP) in same medium. The amount of c-AMP produced in thyroid slices incubated in medium, in which responder cells (8 X 10(5)), was elevated in all 7 untreated cases of Graves' disease, while not elevated in 7 euthyroid cases. The value of % suppression (c-AMP) in euthyroid cases with Graves' disease was significantly higher than that in untreated cases. The value of % suppression (IgG) was reduced and had a significant negative relation with logarithm of serum antimicrosomal antibody titer in patients with Hashimoto's thyroiditis. These results indicate that low activity of suppressor T cell had a role on antibody production, including thyroid stimulating antibody, and pathogenesis of autoimmune thyroid diseases.

Topics: Adult; Autoimmune Diseases; Concanavalin A; Cyclic AMP; Female; Graves Disease; Humans; Immunoglobulin G; Male; Methimazole; T-Lymphocytes, Regulatory; Thyroiditis, Autoimmune; Triiodothyronine

Evidence concerning the role of hyperthyroidism per se in suppressor cell dysfunction in Graves' disease is conflicting. To investigate this issue, we studied the effect of triiodothyronine (T3) administration to ten healthy volunteers for 7 days on spontaneous (short-lived) and Concanavalin A (Con A)-induced suppressor cell activities. The short-lived suppressor cell index is a ratio of [3H] thymidine incorporation induced by Concanavalin A in lymphocytes preincubated for 24 h (to remove adherent cells) to that of non-incubated lymphocytes; the more active the adherent suppressor cells, the higher this index. The mean short-lived suppressor cell index rose from a mean of 2.46 +/- 0.15 (+/- S.D.) before T3 treatment to 3.29 +/- 0.46 (p less than 0.01) after 7 days of T3. Concanavalin A-induced suppressor cell activity, which measures the potential suppressive activity of lymphocytes triggered by Con A is expressed as the percentage decrease in [3H] thymidine incorporation by lymphocytes cultured with Con A for 72 h in relation to that by fresh lymphocytes. Con A-induced suppressor cell activity also improved from 55.8% +/- 2.5 before T3 treatment to 62.4% +/- 1.9 (p less than 0.05) at 7 days of this treatment. These studies show that within the time limitations of the study, T3 appears to enhance short-lived and Concanavalin A-induced suppressor cell activities.

Topics: Adult; Autoantibodies; Autoimmune Diseases; Cells, Cultured; Concanavalin A; Graves Disease; Humans; Lymphocyte Activation; Middle Aged; Receptors, Cell Surface; Receptors, Thyrotropin; T-Lymphocytes, Regulatory; Thyroglobulin; Triiodothyronine

We have been studying the pathogenesis of adjuvant arthritis in rats using a long-term cell line of T lymphocytes, the A2 line, which can induce polyarthritis and can also be used to vaccinate rats against adjuvant arthritis. Although line A2 was selected for its proliferative response to mycobacteria, it also responded to collagen type II. To elucidate its role of responsiveness to collagen type II and the relationship between arthritogenicity and vaccination, we cloned A2 and selected a subline A2b. We now report that subline A2b, which bore a marker of helper/delayed hypersensitivity T lymphocytes, was strongly arthritogenic, but could not vaccinate against arthritis. Moreover, A2b showed no response to collagen type II. Therefore, reactivity to collagen type II is not a requisite for arthritogenicity, and mediation of arthritis and vaccination can be distinct properties of different populations of T lymphocytes.

Topics: Animals; Antigens, Bacterial; Arthritis; Arthritis, Experimental; Autoimmune Diseases; Clone Cells; Collagen; Concanavalin A; Immunity, Innate; Lymphocyte Activation; Mice; Mycobacterium tuberculosis; Phenotype; Rats; Rats, Inbred Lew; T-Lymphocytes; T-Lymphocytes, Helper-Inducer

Total lymphoid irradiation (TLI) at doses of 2200 rads or greater prevented diabetes in susceptible BB/W rats. Two of 29 (7%) treated rats became diabetic compared with 23 of 39 (59%) controls (P less than 0.001). TLI did not, however, prevent insulitis or thyroiditis in nondiabetic rats, nor did it restore the depressed concanavalin-A responsiveness of BB rat lymphocytes. T-lymphocyte subset proportions were the same in both groups. TLI was associated with significant radiation-related mortality, and nondiabetic TLI-treated rats weighed significantly less than controls. We conclude that TLI is effective in the prevention of BB rat diabetes. However, TLI fails to correct the subclinical immunologic abnormalities of the model and is associated with significant morbidity.

Topics: Animals; Autoimmune Diseases; Concanavalin A; Diabetes Mellitus, Type 1; Dose-Response Relationship, Radiation; Female; Islets of Langerhans; Lymphoid Tissue; Male; Mitosis; Pancreatitis; Rats; T-Lymphocytes; Thyroiditis

MRL-lpr/lpr mice and other autoimmune strains that bear the lpr gene develop a profound lymphadenopathy characterized by an expansion of a unique dull Lyt-1+2- T cell population. Because fresh splenic and lymph node T cells from such mice stimulated Con A in vitro are extremely defective in IL 2 production and proliferation, T cell lines derived from MRL-lpr/lpr spleens were established and maintained for several months, and were analyzed for their factor production to define their growth requirements. The results indicate that cultivation in vitro leads to constitutive production of IL 2 and the capacity to respond to growth factors, thereby facilitating the continuous proliferation of T cells bearing the dull Lyt-1+2- phenotype in vitro in the absence of exogenous antigen or mitogen. These studies indicate that MRL-lpr/lpr T cells have the ability to produce IL 2 and to respond to IL 2 with long-term proliferation. In addition, the impaired responsiveness to Con A of fresh MRL-lpr/lpr lymph node T cells was found to be quite transitory, because even short-term culture allowed MRL lpr/lpr T cells to respond normally.

Topics: Animals; Autoimmune Diseases; Cell Line; Concanavalin A; Flow Cytometry; Interleukin-2; Lymph Nodes; Lymphocyte Activation; Mice; Mice, Inbred CBA; Mice, Mutant Strains; Phenotype; Receptors, Immunologic; Receptors, Interleukin-2; T-Lymphocytes

Topics: Animals; Autoimmune Diseases; B-Lymphocytes; Cell Line; Concanavalin A; Humans; Immunity, Cellular; In Vitro Techniques; Interleukin-2; Lymphokines; Macrophages; Mice; Monocytes; Suppressor Factors, Immunologic; T-Lymphocytes

Isoprinosine (IPS) is a new anti-viral agent which appears to have immunomodulatory activities which include its ability to enhance the in vitro blastogenic responses of normal lymphocytes to mitogens. The present study compares the effects of IPS on the in vitro immune functions of peripheral blood mononuclear cells (PBMC) from systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) patients with its effects on PBMC from normal controls. Each mitogen (Con A, PHA or PWM) was used at its optimal concentration with a range of IPS concentrations (0-25 micrograms/ml). PHA-induced blastogenesis by PBMC from all three groups was enhanced by IPS at or above 5 micrograms/ml. The Con A-induced responses of SLE lymphocytes were significantly enhanced over controls by IPS (P less than 0.02 at 5 micrograms/ml) while those of RA lymphocytes were not. IPS had little effect on PWM-induced blastogenesis by RA lymphocytes but did enhance the blastogenic responses of SLE lymphocytes (P less than 0.01 at 5 micrograms/ml). In contrast, the characteristically high immunoglobulin synthesis by SLE lymphocytes was decreased by IPS. The mechanism responsible for these effects is not known but IL-2 production by patient lymphocytes in vitro which was low for both RA (P less than 0.01) and SLE (P less than 0.02) increased significantly (P less than 0.05) when SLE lymphocytes were cultured with IPS. These data identify IPS as an agent for the study of aberrant immune regulation in autoimmune diseases and suggest that it may have potential therapeutic value in SLE.

Topics: Adult; Arthritis, Rheumatoid; Autoimmune Diseases; Cells, Cultured; Concanavalin A; Humans; Immunoglobulins; Inosine; Inosine Pranobex; Interleukin-2; Lupus Erythematosus, Systemic; Lymphocyte Activation; Lymphocytes; Middle Aged; Mitosis; Phytohemagglutinins

Topics: Autoimmune Diseases; Concanavalin A; Humans; Leukocyte Count; Nervous System Diseases; Rosette Formation; T-Lymphocytes, Regulatory

T-Lymphocyte number and functions are often reduced, while B-lymphocyte function is often increased in patients with autoimmune disorders. To study the mechanisms responsible for these T-cell malfunctions in autoimmunity we adapted the murine experimental autoimmune myasthenia gravis (EAMG) model. Splenocytes from C57BL/6 mice immunized with acetylcholine receptors (AChR) in complete Freund's adjuvant (CFA) produced approximately half the amount of concanavalin A (Con A)-induced interleukin 2 (IL-2) as did splenocytes of CFA-inoculated controls. Further, AChR plus CFA-immunized splenocytes showed a marked reduction in T-cell proliferative responses induced by Con A or phytohemagglutinin when compared with CFA-inoculated controls. By contrast, lipopolysaccharide-induced B-cell function is preserved. Deficient Con A splenic T-cell response is seen early after secondary inoculation with CFA or AChR in CFA. T-Cell recovery occurs in CFA-inoculated mice but not in AChR plus CFA-inoculated mice. Defective Con A splenic T-cell response seen early after secondary immunization with CFA or AChR in CFA is due to the presence of a defective splenic adherent cell population. Moreover, defective Con A splenic T-cell response seen after established autoimmunity to AChR in EAMG is also due to the presence of a defective splenic adherent cell population.

Topics: Animals; Autoimmune Diseases; Cell Adhesion; Concanavalin A; Female; Freund's Adjuvant; Immunity, Cellular; Immunization, Secondary; Immunologic Deficiency Syndromes; Interleukin-2; Kinetics; Lymphocyte Activation; Mice; Myasthenia Gravis; Receptors, Cholinergic; Spleen; T-Lymphocytes; T-Lymphocytes, Regulatory

Polymyositis/dermatomyositis (PM/DM) is an autoimmune disorder of unknown aetiology. In order to study whether immunoregulatory abnormalities might be involved in this autoimmune state, we investigated the autologous mixed lymphocyte reaction (AMLR) and concanavalin A-induced suppressor cell function (Con A-induced suppression) in adult patients with primary PM/DM. We found the AMLR to be significantly depressed in patients; responsiveness could not be enhanced by increasing the numbers of non-T stimulator cells in culture, nor by varying the day on which cultures were harvested. Con A-induced suppression of T cell proliferative responses to mitogenic stimuli was normal. These findings implicate abnormal immunoregulation in the pathophysiology of PM/DM. Further, the dissociation of AMLR reactivity from Con A-inducible suppression suggests that events important for immunoregulatory competence may occur in the AMLR culture, despite the absence of an observed proliferative response.

Topics: Adult; Aged; Autoimmune Diseases; Concanavalin A; Dermatomyositis; Dose-Response Relationship, Immunologic; Humans; Leukocyte Count; Lymphocyte Activation; Lymphocyte Culture Test, Mixed; Middle Aged; Myositis; T-Lymphocytes, Regulatory

MRL-lpr mice display immunoregulatory disturbances which are related to an early massive T-lymphocyte hyperplasia. Features of autoimmunity are rapidly progressive and these animals die from immune complex-mediated glomerulonephritis. Previous studies show that 15 methyl prostaglandin E1 (PGE) treatment in MRL-lpr mice prolongs survival by preventing lymphoproliferation and the subsequent renal disease. The present study indicates that a major activity of this therapy stabilizes several T-cell functions. Both the age-related loss of the autologous mixed-lymphocyte reaction (AMLR) (Ly1+ 2,3- dependent) and the concanavalin A-induced suppressor cell activity (Ly1- 2,3+ dependent) remain intact. It is suggested that PGE preserves these T-cell functions by maintaining a more normal balance of T-cell subsets.

Topics: Alprostadil; Animals; Antigen-Antibody Complex; Autoimmune Diseases; Cells, Cultured; Concanavalin A; Immunosuppression Therapy; Lymphocyte Activation; Lymphocyte Culture Test, Mixed; Mice; Mice, Inbred BALB C; Mice, Inbred Strains; Prostaglandins E, Synthetic; Spleen; T-Lymphocytes; T-Lymphocytes, Regulatory

Disturbances in immune interferon (IFN gamma) activity have been implicated in the development of human systemic lupus erythematosus (SLE) and the spontaneous disease sustained by autoimmune-prone mice. We therefore investigated the cellular basis for IFN gamma production in MRL-Ipr/Ipr mice and examined the relationship between synthesis of interleukin 2 (IL 2) and IFN gamma. In vitro IL 2 and IFN gamma production in 3 to 6-mo-old, autoimmune MRL-Ipr/Ipr and MRL-+/+ mice was compared with that seen in age- and sex-matched, immunologically normal CBA/J mice. 5 X 10(6) spleen cells were pulsed with 5 micrograms of concanavalin A (Con A), and the cellfree supernatant was assayed for IL 2 and IFN gamma activity at various times up to 72 hr. We found that peak levels of IL 2 in MRL mice were less than 10% of those in the CBA/J. Yet, production of IFN gamma by cells from the autoimmune and normal strains was quite comparable. The addition of murine IL 2 to optimally Con A-stimulated cells from the MRL-Ipr/Ipr or normal mice did not affect the subsequent peak production of IFN gamma. Although the primary producers of IFN gamma in cultures of normal mice bear the Lyt-2+ phenotype, the Lyt-1+2- T-cell subset was found to be the principal source of IFN gamma in the aged MRL-Ipr/Ipr. These data suggest that Lyt-1+ cells from MRL-Ipr/Ipr mice may be differentially responsive to the signal delivered by the same mitogenic lectin with respect to lymphokine production and may indicate a distorted commitment of such cells toward production of IFN gamma and repression of IL 2 synthesis. The relationship between hypoproduction of IL 2, this usual source of IFN gamma, and the autoimmune disease sustained by MRL-Ipr/Ipr mice remains unclear.

Topics: Animals; Autoimmune Diseases; Concanavalin A; Female; Immunity, Cellular; Interferon-gamma; Interleukin-2; Mice; Mice, Inbred CBA; Mice, Mutant Strains; Phenotype; Spleen; T-Lymphocytes

Lymph node and spleen cells of the autoimmune MRL/Mp-lpr/lpr mouse strain spontaneously produce (in the absence of mitogenic stimulation) a factor(s) that induces B cell differentiation. This factor is not produced by the congenic MRL/n mouse strain that lacks the lpr gene or by normal mouse strains. However, lymphoid cells of the B6-lpr/lpr (B6/1) strain also produce a B cell differentiation factor. Although the factor acts on resting B cells, its effect is greatly magnified by activating the B cells with anti-mu or lipopolysaccharide. MRL/l mice begin producing the factor as early as 1 mo of age but levels increase with age and appearance of lymphoproliferation. Cell depletion studies reveal that this factor is produced by T cells of the Lyt-1+2-phenotype. Because of its association with the lpr/lpr genotype, we term this B cell differentiation factor L-BCDF. Functional analysis of L-BCDF reveals that it acts regardless of cell density in culture and in the absence of interleukin 2 (IL-2). In fact, the increase in the production of L-BCDF by MRL/1 T cells with aging occurs concomitantly with a marked decrease in their ability to produce IL-2. No T cell replacing factor activity or B cell growth factor-like activity can be detected in MRL/l-derived supernatants. L-BCDF induces both IgM and IgG synthesis in lipopolysaccharide-activated B cells; however, it has a greater effect on IgG secretion. In particular, the production of IgG1, IgG2a, and IgG2b are markedly enhanced in the presence of L-BCDF. The spontaneous production of L-BCDF by T cells of SLE mice of lpr/lpr genotype suggests an association of this factor with autoimmunity.

Topics: Aging; Animals; Autoimmune Diseases; B-Lymphocytes; Concanavalin A; Female; Genotype; Growth Substances; Immunoglobulin G; Immunoglobulin M; Interleukin-2; Interleukin-4; Lupus Erythematosus, Systemic; Lymphocyte Activation; Lymphokines; Mice; Mice, Inbred BALB C; Mice, Inbred C3H; Mice, Inbred C57BL; Mice, Mutant Strains; T-Lymphocytes

Topics: Adolescent; Adult; Aged; Autoimmune Diseases; Child; Child, Preschool; Concanavalin A; Humans; Immunity, Cellular; Lymphocyte Activation; Middle Aged; Phytohemagglutinins; Platelet Count; Purpura, Thrombocytopenic; Rosette Formation; T-Lymphocytes

The effect of concanavalin A (Con A) and/or phorbol myristate acetate (PMA) on interleukin 2 (IL 2) production and tritiated thymidine incorporation was measured in young (6 weeks) and old (16-24 weeks) autoimmune mice by pulsing 5 X 10(6) unfractionated spleen cells with 5 micrograms of Con A and/or 5 ng of PMA for variable periods of time. The apparent deficiency in Con A-stimulated IL 2 production manifested by mice prone to the development of autoimmune disease was repaired by the addition of PMA. PMA did not enhance interleukin 1 (IL 1) secretion in autoimmune MRL-lpr mice either alone or in combination with Con A. The addition of purified IL 1 to Con A-pulsed autoimmune cells did not increase IL 2 production. Freeze-thaw experiments suggested that PMA does not promote IL 2 synthesis. Con A-pulsed cells plus PMA-pulsed cells do not syngergize. These data indicate that autoimmune-prone mice are capable of producing IL 2 and of proliferating in response to Con A provided the comitogen PMA is present. It can be argued that the failure to produce IL 2 or to respond to proliferative signals is not fundamental to the development of the disease sustained by autoimmune-prone mice.

Topics: Animals; Autoantibodies; Autoimmune Diseases; Concanavalin A; DNA Replication; Interleukin-2; Lymphocyte Activation; Lymphocytes; Mice; Mice, Inbred Strains; Tetradecanoylphorbol Acetate

Using peripheral blood lymphocytes from 8 healthy individuals and 5 patients with untreated Graves' disease, direct effects of methimazole (MMI) and propylthiouracil (PTU) on lectin-induced lymphocyte proliferative response were studied. Lymphocytes were cultured for 72 hr in the presence of lectins and antithyroid drugs. Lymphocyte DNA synthesis was counted by incorporation of 3H-thymidine. MMI at 1,000 microM enhanced lectin-induced lymphoproliferation of peripheral blood lymphocytes from both patients with Graves' disease and healthy individuals, at every point of culture time, while PTU showed a tendency toward suppression. These results suggest that this lympho-stimulation by MMI may be a causative factor related to insulin autoimmune syndrome, as deduced from the clinical reports that insulin autoimmune syndrome is, sometimes, found in patients with Graves' disease treated with MMI. This lympho-stimulation was evident regardless of the time of MMI addition, thus indicating that MMI is, by its action, a lymphoid stimulator and may lead to the insulin autoimmune syndrome in predisposed subjects with underlying Graves' disease.

Topics: Autoimmune Diseases; Concanavalin A; Graves Disease; Humans; Insulin Antibodies; Lymphocyte Activation; Methimazole; Phytohemagglutinins; Pokeweed Mitogens; Propylthiouracil; Syndrome

The present investigation shows that autoreactive effector cells that transfer experimental allergic encephalomyelitis (EAE) can be activated from spleens and lymph nodes of Lewis rats given a single injection of 25 micrograms myelin basic protein (BP) in incomplete Freund's adjuvant (IFA), despite the fact that the cell donors do not develop EAE. Rather, these donor rats are unresponsive to EAE when given an encephalitogenic emulsion of BP in complete Freund's adjuvant (CFA). Lymphoid cells from rats given a single injection of BP-IFA were almost as effective as cells from BP-CFA-treated rats with respect to transferring EAE after in vitro activation with BP or concanavalin A (Con A). Irrespective of whether donors received BP in IFA or CFA, BP-cultured spleen and lymph node cells (SpC and LNC, respectively) transferred EAE, whereas Con A-cultured SpC but not LNC exhibited effector cell activity. Con A-cultured LNC were able to transfer EAE if the cultures were reconstituted with irradiated adherent phagocytic cells (which could be obtained from normal Lewis rat spleens) or with conditioned medium from these adherent SpC. These findings indicate that accessory cells are required for in vitro induction of this T cell-mediated autoimmune response.

Topics: Adjuvants, Immunologic; Animals; Autoimmune Diseases; Concanavalin A; Encephalomyelitis, Autoimmune, Experimental; Female; Immunity, Cellular; Lymph Nodes; Lymphocyte Activation; Myelin Basic Protein; Rats; Rats, Inbred Lew; Spleen

Peripheral blood lymphocytes from 30 patients with rheumatoid arthritis and 14 controls were examined for suppressor activity by two different assays. These were the Concanavalin-A-induced and the short-lived suppressor cell assays. There was no difference in suppressor activity between patients and controls, the suppressor activity of HLA-DR3 positive patients was no less than that of non-DR3 patients. However, patients with nodules showed reduced suppression in the short-lived suppressor cell assay when compared with patients without nodules.

Topics: Adult; Arthritis, Rheumatoid; Autoimmune Diseases; Concanavalin A; Female; Histocompatibility Antigens Class II; HLA-DR3 Antigen; Humans; Immunoassay; Male; Middle Aged; T-Lymphocytes, Regulatory

Suppressor lymphocyte function was evaluated in control subjects and in patients with autoimmune thyroid disease, utilizing an assay in which indomethacin was added to lymphocyte cultures to inhibit prostaglandin-producing suppressor cells. This assay is based on the observation that the addition of indomethacin, a potent prostaglandin synthesis inhibitor, to phytohemagglutinin-stimulated peripheral blood lymphocytes should cause an increase in the incorporation of iododeoxyuridine in control subjects and a smaller increase in diseases with reduced prostaglandin-producing suppressor cells. The addition of indomethacin, 1 microgram/ml, stimulated iododeoxyuridine incorporation in phytohemagglutinin-stimulated cultures in control subjects to an index value of 1.43 (i.e., the increment in iododeoxyuridine incorporation with both indomethacin and phytohemagglutinin was 43% greater than the incorporation with phytohemagglutinin alone). The stimulation index was significantly lower in patients with Graves' disease who were toxic and untreated (1.18 +/- 0.25, mean +/- SD; P less than 0.003). Patients who were toxic while receiving antithyroid drugs or after radioiodine therapy or patients euthyroid after treatment had a mean stimulation index in the normal range, although the spread of data was very large in these groups. Responses in patients with Hashimoto's thyroiditis were also quite variable. The average response was 1.74 +/- 0.72, with 40% of the patients showing a high stimulation index. This study supports our previous investigations in which we used different assay systems for measuring suppressor-cell function in patients with thyroid autoimmune diseases and indicates that a defect in suppressor lymphocyte function is measureable by another technique. The abnormality persists in some cases after metabolic control has been achieved, but usually returns toward normal over months or years.

Topics: Adolescent; Adult; Aged; Autoimmune Diseases; Cell Adhesion; Concanavalin A; Female; Graves Disease; Humans; In Vitro Techniques; Indomethacin; Lymphocyte Activation; Male; Middle Aged; Phytohemagglutinins; Prostaglandins; T-Lymphocytes, Regulatory; Thyroiditis, Autoimmune

Patients with multiple sclerosis and matched controls were tested for lymphocyte stimulation response and induction of suppressor cell activity in response to concanavalin A (Con A) and antigens from axolemma or myelin. Of 17 stable patients, 6 failed to have a suppressor cell response activated by one of these brain cell antigens. Among the patients who lacked these suppressor responses, five had lymphocyte stimulation responses to the same antigens. All matched controls except for one had suppressor cell responses to these antigens and none responded with a positive cellular immune reaction. We found no difference in lymphoproliferative responses to Con A in patients and controls. The level of suppressor cell activity induced by Con A in the stable MS patients varied but did not differ significantly from that of controls.

Topics: Antigens; Autoantibodies; Autoimmune Diseases; Axons; Brain; Concanavalin A; Humans; Liver; Lymphocyte Activation; Microsomes; Multiple Sclerosis; Myelin Sheath; T-Lymphocytes, Regulatory

In the studies reported here, we have analyzed the production and consumption of T cell growth factor, more recently termed interleukin 2 (IL-2), as well as some cell-mediated immune functions, in murine strains [MRL, BXSB, NZB, and (NZB x NZWF1] manifesting systemic lupus erythematosus (SLE)-like syndromes. Young (4-6 wk) or old (4-8 mo) autoimmune or normal mice were studied and compared with regard to the following T cell functions in vitro after stimulation with concanavalin A (Con A): (a) mitogenic response; (b) IL-2 levels in culture supernates; and (c) the ability to respond to and adsorb IL-2. In addition, proliferative activity in the allogeneic mixed leukocyte culture and frequency of alloreactive cytotoxic T lymphocyte precursors (CTLp) were analyzed in some of these strains. Reduced Con A-induced mitogenic responses and IL-2 production appeared at 3-6 wk of age in the early, severe SLE developing strains MRL-Mp-lpr/lpr (MRL/l) and male BXSB and progressed thereafter. Similar defects appeared at a later stage in MRL/Mp-+/+ and (NZB x NZW)F1 hybrid mice, which develop late disease. Detailed analysis of cells from the enlarged lymph nodes and spleens of older MRL/l mice demonstrated that such cells: (a) responded poorly to Con A or allogeneic stimulator cells, even in the presence of exogenous IL-2; (b) did not suppress IL-2 production by normal spleen cells; (c) were relatively incapable of adsorbing or inactivating IL-2; and (d) had a markedly reduced anti-H-2b CTLp frequency in the mesenteric lymph nodes but a normal one in spleen. These results indicate that the proliferating Thy-1.2+, Lyt-1+ T cells in MRL/l mice are defective in their responses to mitogenic stimuli, in IL-2 production, and in expression of acceptor sites for IL-2. The relevance of these defects to the MRL/l disease as well as to the role of IL-2 in autoimmunity in general remains to be determined.

Topics: Age Factors; Animals; Autoimmune Diseases; Cells, Cultured; Concanavalin A; Disease Models, Animal; Immune Tolerance; Interleukin-2; Lymphocyte Activation; Lymphokines; Mice; Mice, Inbred Strains; Spleen; T-Lymphocytes; T-Lymphocytes, Regulatory

Defective suppressor cell function may be a causative factor in autoimmune disease in animals and man. In autoimmune thyroid disease, decreased suppressor cell activity could, under appropriate conditions, account for excess production of thyroid autoantibodies. We evaluated suppressor cell function in patients with Graves' disease and Hashimoto's thyroiditis and in normal controls. The method used is based on the principle that immunoglobulin synthesis by pokeweed mitogen (PWM)-stimulated lymphocytes is inhibited by Concanavalin A (Con A) stimulation of suppressor T cells. We studied suppressor cell control of polyclonal immunoglobulin G (IgG) and the thyroid-specific autoantibody, antimicrosomal antibody. PWM-stimulated IgG secretion (mean +/- SD) by lymphocytes from patients with Graves' disease (2797 +/- 718 ng/ml) and Hashimoto's thyroiditis (2201 +/- 423 ng/ml) did not differ from normal subjects (2431 +/- 485 ng/ml). The addition of Con A to PWM-stimulated lymphocytes suppressed IgG production in all three groups: Graves', 475 +/- 137 ng/ml; Hashimoto's, 507 +/- 74 ng/ml; and normal subjects, 460 +/- 156 ng/ml. The degree of suppression by the disease groups did not differ from the normal controls. Antimicrosomal antibody was detected in the concentrated, PWM-stimulated culture media of two of four Hashimoto's lymphocytes, three of five Graves' lymphocytes, and none of nine normal controls. Con A induced marked suppression of this organ-specific antibody in all cases. We conclude that Con A-stimulated lymphocytes from patients with Hashimoto's thyroiditis and Graves' disease can suppress antimicrosomal antibody and polyclonal IgG synthesis. These findings do not support the postulate of a generalized defect of suppressor cell function in these thyroid disorders.

Topics: Adult; Autoantibodies; Autoimmune Diseases; Concanavalin A; Female; Graves Disease; Humans; Immunoglobulin G; Male; Microsomes; Middle Aged; Pokeweed Mitogens; T-Lymphocytes, Regulatory; Thyroiditis, Autoimmune

Lysosome proteins derived from peripheral blood granulocytes of patients with multiple sclerosis (MS), lupus erythematosus (LE), rheumatoid arthritis (RA) and recurrent uveitis cause the impairment of Con A-induced suppressor cell activity in two-step culture in vitro. This effect is independent of lysosome protease activity. Such a phenomenon, observed in vitro, may cause disturbances in suppressor cell function in the course of the above diseases.

Topics: Adult; Arthritis, Rheumatoid; Autoimmune Diseases; Concanavalin A; Female; Humans; Isoflurophate; Lupus Erythematosus, Systemic; Male; Middle Aged; Multiple Sclerosis; Neutrophils; Proteins; Recurrence; T-Lymphocytes, Regulatory; Uveitis

Suppressor-cell function was evaluated by two in-vitro assay systems in forty patients with intraocular inflammatory disease (uveitis) and in sixteen healthy age-matched controls. A concanavalin-A (Con A)-induced suppressor-cell assay showed that patients with posterior uveitic conditions had greater suppressor activity than did the anterior uveitic group or the control group (p < 0.005); but an assay for non-induced suppressor-cell activity showed that the posterior uveitic group had less suppressor activity (p < 0.001). These findings suggest (a) that at least two cell types may be involved in immunoregulation, and (b) that not all diseases of presumed autoimmune origin are the result of reduced suppressor activity, which has been shown in some "autoimmune" conditions.

Topics: Adult; Autoimmune Diseases; Choroid; Ciliary Body; Concanavalin A; Female; Humans; Iris; Male; T-Lymphocytes, Regulatory; Uveitis

We have investigated in vitro the magnitude, nature, and regulation of spontaneous and mitogen-induced Ig secretion by splenic lymphocytes from several autoimmune murine strains (NZB, NZB X W, MRL/l BXSB) and appropriate, normal mice. All autoimmune strains had increased numbers of mature splenic B lymphocytes, which secreted and/or contained Ig, compared to age-matched normal strains. In NZB and NZB X W mice, the high frequency of mature B cells was apparent early in life, whereas in MRL/l and BXSB mice it was first noted shortly before the clinical onset of disease. Spleen cells from young autoimmune mice of all four strains secreted predominantly IgM, but with aging and the appearance of disease, the cells switched to IgG secretion predominantly. In contrast, spleen cells from normal mice were predominantly IgM, but with aging and the appearance of disease, the cells switched to IgG secretion predominantly. In contrast, spleen cells from normal mice were predominantly IgM secretors throughout the animals' lives. Approximately 15% of the total Ig-secreting cells in older NZB, NZB X W, and MRL mice were committed to secretion of anti-ssDNA antibodies. In both autoimmune and normal spleen cells, the B-cell population alone contained fewer secreting cells than the total lymphocyte population, indicating that T cells were required to achieve maximal levels of plaque-forming cells. Spleen cells of NZB and NZB X W mice had a greater response to lipopolysaccharide (LPS) than other autoimmune and normal strains. Responsiveness to LPS, as measured by the frequency of induced Ig-secreting cells, was considerably diminished with age and onset of disease in all autoimmune but not in normal strains. LPS-induced Ig secretion by B cells of autoimmune and normal mice was subject to regulation by splenic T cells. No significant differences were observed between concanavalin-A (Con A) stimulated spleen cells from young and older autoimmune mice and normal control strains in effectively suppressing spontaneous and LPS-induced Ig secretion. Moreover, B cells from autoimmune mice and from normal strains were equally receptive to Con A-induced suppressor signals. T cells from young and older NZB and BXSB mice added to a standard number of B cells from syngeneic young mice provided equal help in enhancing LPS-induced Ig secretion, and this help in turn was equivalent to that provided by T cells from normal mice of the same H-2 haplotype. The exception was the MRL/l strain; T

Topics: Animals; Autoantibodies; Autoimmune Diseases; B-Lymphocytes; Cell Differentiation; Concanavalin A; Female; Immunoglobulins; Lipopolysaccharides; Lupus Erythematosus, Systemic; Male; Mice; Mice, Inbred NZB; Spleen; T-Lymphocytes; T-Lymphocytes, Regulatory

Topics: Agammaglobulinemia; Animals; Autoimmune Diseases; Chickens; Concanavalin A; Humans; Immunologic Deficiency Syndromes; Lymphocyte Cooperation; Macrophages; Mice; Mycoses; Neoplasms; Prostaglandins; T-Lymphocytes; T-Lymphocytes, Regulatory

Because female NZB/NZW mice develop autoimmune abnormalities similar to those encountered in human systemic lupus erythematosus (SLE), a group of female NZB/NZW mice were used to study mechanisms of autoimmunity. These mice were treated daily with an immune suppressive material, 0.5 ml of a concanavalin A-stimulated spleen cell supernate (CONS), starting at 30 weeks of age after induced remission with prednisolone. This CONS treatment effectively reduced the proteinuria and the severity of the renal lesions, but failed to reduce the serum anti-DNA antibody level. Thus, the CONS effect on the autoimmunity in the NZB/NZW mice in induced remission appears to result from a more complicated mechanism than reduction in serum anti-DNA antibody level.

Topics: Animals; Antibodies, Antinuclear; Autoimmune Diseases; Concanavalin A; Crosses, Genetic; Culture Media; DNA; Female; History, 20th Century; Kidney; Methylprednisolone Hemisuccinate; Mice; Mice, Inbred NZB; Proteinuria; Spleen; T-Lymphocytes

Topics: Aging; Animals; Autoimmune Diseases; Blood Cells; Cell Division; Cell Separation; Concanavalin A; Dog Diseases; Dogs; Female; Immunity, Cellular; Lymph Nodes; Lymphocytes; Male; Mitogens; Myelin Proteins; Phytohemagglutinins; Spinal Cord; Spinal Cord Diseases; Spleen; Thymus Gland

Topics: Adult; Autoimmune Diseases; Concanavalin A; Female; Histamine; HLA Antigens; Humans; Hydrocortisone; Indomethacin; Male; Middle Aged; Phytohemagglutinins; Prostaglandins; Prostaglandins E; Thymidine

Lymphocyte chalone from the spleens of old BALB/c, young BALB/c and young NZB mice caused significant suppression of the proliferative response of BALB/c and NZB spleen cells to T and B mitogens, whereas lymphocyte chalone from old NZB spleen did not suppress. Lymphocyte chalone from young and old NZB mice was tested using different ages of NZB/NZW responding spleen cells; at all ages concanavalin A- and lipopolysaccharide-induced proliferation was suppressed less by the chalone from old NZB mice than from that of young NZB mice. The responding NZB/NZW cells were suppressed equivalently at all ages studied. The basis for the loss of lymphocyte chalone activity in old NZB mice remains unknown; however, it appears likely that this event has a role in the disturbance of the negative feedback control system which contributes to NZB autoimmune disease.

Topics: Aging; Animals; Autoimmune Diseases; Concanavalin A; Growth Inhibitors; Immunosuppression Therapy; Lymphocyte Activation; Lymphocytes; Mice; Mice, Inbred BALB C; Mice, Inbred NZB; Spleen

We studied a five-year-old girl with several autoimmune disorders and a 16-year-old boy with acquired agammaglobulinemia to determine whether aberrations of immunoregulatory T cells could explain some instances of immunodeficiency or autoimmunity. The normal peripheral blood T-cell population, as defined by specific heteroantiserums, is 20 per cent TH2+ and 80 per cent TH2-. Human suppressor cells are TH2+, whereas helper cells are TH2-. In addition, each subset expresses Ia antigens upon activation. Our patient with autoimmune disease had no demonstrable TH2+ cells, and her lymphocytes could not be induced to suppress. Her circulating T cells were of an activated-helper phenotype, i.e., TH2-,Ia+. In contrast, in the boy with agammaglobulinemia, the T-cell population was predominantly of an activated-suppressor phenotype, i.e., TH2+,Ia+. This patient's T cells abrogated both his own and his histoidentical brother's B-cell secretion of immunoglobulins. We conclude that the characterization of T cells may provide insight into the causes of a number of abnormal immune states in man.

Topics: Adolescent; Agammaglobulinemia; Autoimmune Diseases; B-Lymphocytes; Cell Separation; Child, Preschool; Concanavalin A; Female; Hemolytic Plaque Technique; Humans; Immunoglobulins; Lymphocyte Activation; Male; Mitogens; T-Lymphocytes; T-Lymphocytes, Regulatory

Antibodies to T cells present in the plasma of patients with active systemic lupus erythematosus (SLE) plus complement are able to eliminate concanavalin A-induced suppressor function for the proliferative responses of T cells to allogeneic lymphocytes (MLR) and of B cells to pokeweed mitogen (PWM). Such antibodies were found to be effective in eliminating suppressor function only when T cells were treated before activation; there was no effect when treatment was performed after activation. These studies indicate that the antibodies preferentially interact with a T cell necessary for the generation of suppressor cells, rather than with mature, activated suppressor cells. Studies of individual SLE patients indicate that the same defects observed in SLE T cells were induced in normal T cells by plasma from that patient. Such observations suggest that many T-cell defects associated with active SLE may not be intrinsic T-cell abnormalities, but, rather, secondary effects of anti-T-cell antibodies. Studies of the T-cell subpopulations responsible for suppression of the MLR and PWM responses indicate that only T gamma cells (T cells bearing receptors for the Fc portion of immunoglobulin [Ig]G) acted as precursors of suppressor cells for the MLR, whereas both T gamma and T non-gamma cells (T cells not bearing receptors for the Fc portion of IgG) could be activated to suppress the PWM response. Consistent with this observation, SLE anti-T-cell antibodies that preferentially killed T gamma cells preferentially eliminated suppressor cells for the MLR.

Topics: Autoantibodies; Autoimmune Diseases; Cells, Cultured; Concanavalin A; Humans; Immunoglobulin G; Lupus Erythematosus, Systemic; Pokeweed Mitogens; Receptors, Concanavalin A; Receptors, Fc; Receptors, Mitogen; T-Lymphocytes, Regulatory

Topics: Animals; Autoimmune Diseases; B-Lymphocytes; Cell Membrane; Concanavalin A; Fluorescent Antibody Technique; Humans; Immunologic Capping; Leukocyte Count; Lymphocyte Activation; Lymphocytes; Phytohemagglutinins; Purpura, Thrombocytopenic; Rabbits; T-Lymphocytes

Topics: Animals; Autoimmune Diseases; Concanavalin A; Female; Kidney Diseases; Lipopolysaccharides; Mice; Mice, Inbred Strains; ortho-Aminobenzoates; T-Lymphocytes; Time Factors

We have studied peripheral blood mononuclear cells obtained from 24 patients with acute or chronic active hepatitis to determine if there was an abnormality in concanavalin A-induced suppressor cell activity compared to control subjects. Suppressor cells were generated by preincubation of the mononuclear cells with a mitogenic concentration of concanavalin A (6 mug/ml) for 48 hr followed by treatment with mitomycin C and alpha-methyl mannoside. Suppressor cell activity was assessed in second cultures by inhibition of concanavalin A-stimulated blast transformation of fresh allogeneic lymphocytes. Concanavalin A-stimulated suppressor activity was not elicited in mononuclear cells from the majority of patients with chronic active hepatitis in contrast to patients with acute hepatitis or acute inflammatory diseases and controls (P < 0.001). This finding was demonstrable in chronic active hepatitis patients in remission and relapse, both on and off prednisone therapy, and varied considerably during the course of the disease. The extent of liver injury was not related to the measured suppressor cell activity. These studies suggest that in chronic active hepatitis, a disease in which the host immune response may be involved, there appears to be a defect in concanavalin A-stimulated suppressor cells.

Topics: Acute Disease; Adult; Aged; Aspartate Aminotransferases; Autoimmune Diseases; Chronic Disease; Concanavalin A; Female; Hepatitis; Humans; Immunosuppression Therapy; Lymphocyte Activation; Male; Middle Aged

Loss of suppressor T cells was demonstrated in NZB/W mice, an animal model of autoimmunity. As NZB/W mice matured they lost splenic T cells that could be activated by concanavalin A (Con A) to become suppressor cells and lost the ability to produce the regulator of humoral immune responses, soluble immune response suppressor (SIRS). However, NZB/W spleen cells retained the capacity to respond to suppressor signals from Con A pulsed normal spleen cells. Thrice weekly administration of SIRS containing supernatants of Con A pulsed normal spleen cells to young NZB/W mice lead to a striking reduction in the manifestations of autoimmunity.

Topics: Aging; Animals; Autoimmune Diseases; Concanavalin A; Female; Immunoglobulin M; Immunosuppression Therapy; Lymphocyte Depletion; Mice; Mice, Inbred BALB C; Mice, Inbred NZB; Mitogens; Spleen; T-Lymphocytes

Spleen cells from normal mice were cultured with Concanavalin A to produce an immunosuppressive supernate. This supernate was used to treat the lupus-like autoimmune disease of NZB/NZW mice. Such treated mice lived significantly longer than did controls, but only if treatment was initiated early in the course of the illness.

Topics: Age Factors; Animals; Autoimmune Diseases; Cell Extracts; Cells, Cultured; Concanavalin A; Evaluation Studies as Topic; Female; Immunosuppressive Agents; In Vitro Techniques; Lupus Erythematosus, Systemic; Mice; Mice, Inbred Strains; Molecular Weight; Spleen; Stimulation, Chemical; Time Factors; Tissue Extracts

Topics: Adolescent; Adult; Arthritis, Rheumatoid; Autoimmune Diseases; Concanavalin A; Humans; Lectins; Lupus Erythematosus, Systemic; Lymphocytes; Middle Aged

We have investigated suppressor T-cell activity in female NZB/NZW F1 mice using PWM-driven IgM biosynthesis in vitro as an indicator system. In initial we studied we observed that spleen cells from normal mice (BALB/c, C57BL/6), as well as from young (4 wk) and adult (18 wk) NZB/NZW mice, cultured in the presence of PWM synthesize 860 +/- 120 ng IgM/10(6) cells/7 days. However, when Con A (at 2 mug/ml) was added directly to the cultures (along with PWM), cells obtained from adult normal mice and young NZB/NZW mice showed a 94% suppression of IgM synthesis, whereas cells obtained from adult NZB/NZW mice were suppressed significantly less. To analyze these findings we studied the effect of Con A-induced suppressor cells (cells cultured with Con A for 24 h and washed free of Con A) on PWM-driven IgM biosynthesis. Spleen cells obtained from normal mice cultured in the presence of Con A-pulsed cells obtained from normal mice and young NZB/NZW mice showed an 83-88% suppression of PWM-driven IgM synthesis. Similarly, supernates obtained from Con A-pulsed cells of normal mice or of young NZB/NZW mice suppressed PWM-driven IgM synthesis. This suppression by Con A-pulsed cells and their supernates required T cells since T-cell fractions but not B-cell fractions eluted from anti-Fab Sephadex columns mediated suppression of co-cultured normal cells; in addition, Con A-pulsed cells treated with anti-theta and complement do not mediate suppression. These studies of Con A-induced suppressor cell activity in normal mice and young NZB/NZW mice contrast with studies of Con A-induced suppressor cell activity in adult NZB/NZW mice. We found that adult NZB/NZW Con A-pulsed cells and supernates obtained from the Con A-pulse cells had vastly decreased suppressor potential; in this case the Con A-pulse cells and supernatant fluids derived from such cells did not suppress PWM-driven IgM synthesis by normal cells. Finally, whereas spleen cells from young and adult NZB/NZW mice differ in their suppressor cell potential, cells from both sources could respond equally to suppressor signals in that Con A-pulsed normal cells or supernates derived from such cells caused equivalent suppression of PWM-driven IgM synthesis by young and adult NZB/NZW cells. These observations allow us to conclude that NZB/NZW mice lose suppressor T-cell activity as they age.

Topics: Age Factors; Animals; Antibody Formation; Autoimmune Diseases; B-Lymphocytes; Concanavalin A; Female; Hybridization, Genetic; Immunoglobulin M; Immunosuppression Therapy; Mice; Mice, Inbred NZB; Spleen; T-Lymphocytes

Since the blood and thymus of patients with myasthenia gravis may contain inhibitors of neuromuscular transmission that affect acetylcholine receptors of striated muscle, we used denervated rat muscle to test for inhibitors in 43 serums and 18 thymus glands from such patients. Seven per cent of serums inhibited the binding of 125l alpha-bungarotoxin to triton-solubilized receptors; 65 per cent interfered with binding of toxin-labeled receptors to concanavalin-A coupled to Sepharose gel, and 85 per cent formed IgG-receptor complexes detectable by immunoprecipitation. Serum inhibitory activity varied widely among patients with similar clinical manifestations and was not correlated with duration of myasthenia gravis or thymectomy. Among thymus extracts, 44 per cent were inhibitory in the concanavalin-A binding assay, whereas 72 per cent contained anti-receptor IgG. Thus, serums from patients with myasthenia gravis contain more than one anti-receptor factor.

Topics: Acetylcholine; Animals; Autoantibodies; Autoimmune Diseases; Binding Sites, Antibody; Bungarotoxins; Chromatography; Concanavalin A; Female; Humans; Immunoglobulin G; Male; Methods; Muscles; Myasthenia Gravis; Rats; Receptors, Cholinergic; Thymus Extracts; Thymus Gland

Topics: Adolescent; Adrenal Gland Diseases; Animals; Antibody Formation; Antibody-Producing Cells; Autoimmune Diseases; B-Lymphocytes; Concanavalin A; Cytotoxicity Tests, Immunologic; Female; Genital Diseases, Female; Gonads; Humans; Immunity; Immunoglobulin Fc Fragments; Immunoglobulin G; Lectins; Lymphocytes; Mitogens; Sheep; T-Lymphocytes; Thyroid Diseases

Chloroquine increases the inhibition of cultured lymphocytes by high concentrations of phytohemagglutinin (PHA) or concanavalin A (Con A). The inhibition is also increased by complement. Thus chloroquine and complement have similar effects. Time-course studies show that chloroquine increases the rate of onset of the complement-dependent inhibition. In serum preheated to inactivate complement, chloroquine can partially simulate the effect of complement. It is suggested that at certain stages in malaria or autoimmune disease the rate of clearance of parasitized erythrocytes or autoreactive lymphocytes is limited by the concentration of complement. Under these conditions a drug such as chloroquine, which could enhance or simulate the action of complement, might be of therapeutic value.

Topics: Animals; Autoimmune Diseases; Cells, Cultured; Chloroquine; Complement System Proteins; Concanavalin A; Dose-Response Relationship, Drug; Female; Hot Temperature; Humans; Lectins; Lymphocyte Activation; Lymphocytes; Malaria; Rats

Topics: Animals; Autoimmune Diseases; Concanavalin A; Erythrocytes; Humans; Immune Adherence Reaction; Lectins; Lymphocyte Activation; Lymphocytes; Sheep; T-Lymphocytes; Thymidine; Tritium