bromochloroacetic-acid and Autoimmune-Diseases

Psoriasis is strongly associated with streptococcal throat infection, and patients have increased occurrence of such infections. Psoriatic lesional T cells are oligoclonal, and T cells recognizing determinants common to streptococcal M-protein and keratin have been detected in patients' blood. We propose that CD8(+) T cells in psoriatic epidermis respond mainly to such determinants, whereas CD4(+) T cells in the dermis preferentially recognize determinants on the streptococcal peptidoglycan that might itself act as an adjuvant. The streptococcal association might reflect the concurrence of superantigen production promoting skin-homing of tonsil T cells, M-protein mimicking keratin determinants, and adjuvant effects of the peptidoglycan. Accordingly, improvement of psoriasis after tonsillectomy should be associated with fewer T cells that recognize keratin and streptococcal determinants.

Topics: Antigens, Bacterial; Autoimmune Diseases; Bacterial Outer Membrane Proteins; Carrier Proteins; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Dermis; Epidermis; Humans; Keratins; Molecular Mimicry; Palatine Tonsil; Peptidoglycan; Psoriasis; Streptococcal Infections; Streptococcus; Superantigens; Tonsillitis

Peripheral blood cytology and acute phase reactants are used to distinguish between non-inflammatory and inflammatory rheumatic diseases, whereas chronic phase reactants and immunoglobulins can give guidance in distinguishing acute from chronic inflammatory conditions. The complicated path to a well-defined diagnosis of rheumatic disease involves autoimmune serology. This review puts special emphasis on the rational use of autoantibody results for diagnosis, prognosis, planning of follow-up, and estimating the need for therapy. A clinically important use of serodiagnostics can only be implemented by a close collaboration between clinicians and laboratory specialists. A tentative diagnosis is the best basis for ordering and interpreting laboratory results.

Topics: Antibodies, Antineutrophil Cytoplasmic; Antibodies, Antinuclear; Antibodies, Antiphospholipid; Autoantibodies; Autoimmune Diseases; Diagnosis, Differential; Follow-Up Studies; Humans; Immunologic Techniques; Keratins; Prognosis; Rheumatic Diseases; Rheumatoid Factor; Serologic Tests

The epidermis of skin and the oral mucosa are highly specialized stratified epithelia that function to protect the body from physical and chemical damage, infection, dehydration, and heat loss. To maintain this critical barrier, epithelial tissues undergo constant renewal and repair. Epithelial cells (keratinocytes) undergo a program of terminal differentiation, expressing a set of structural proteins, keratins, which assemble into filaments and function to maintain cell and tissue integrity. Two types of cell adhesion structures, desmosomes and hemidesmosomes, function to glue keratinocytes to one another and to the basement membrane, and connect the keratin cytoskeleton to the cell surface. Keratinizing epithelia such as the epidermis and oral gingiva that have to withstand severe physical and chemical forces produce a toughened structure, the cornified cell envelope. This envelope is a major component of the epithelial barrier at the tissue surface. This article summarizes our current understanding of the structure and function of these different cellular components and discusses various genetic and acquired diseases that alter tissue integrity and barrier function. We also highlight recent work demonstrating how loss or attenuation of certain proteases can lead to early onset periodontitis and tooth loss as well as other epithelial abnormalities.

Topics: Autoimmune Diseases; Cadherins; Desmosomes; Epidermolysis Bullosa; Epithelial Cells; Humans; Keratins; Mouth Mucosa; Mutation

Topics: Air Pollution; Anti-Allergic Agents; Autoantigens; Autoimmune Diseases; Child; Child, Preschool; Comorbidity; Complementary Therapies; Environmental Exposure; Female; Forecasting; Genetic Predisposition to Disease; Germany; Global Health; Humans; Hypersensitivity, Immediate; Immunoglobulin E; Infant; Infant Food; Keratins; Male; Prevalence; Respiratory Hypersensitivity; Risk Factors; Th2 Cells

Topics: Autoimmune Diseases; Bile Ducts, Intrahepatic; Cytoskeleton; Humans; Inclusion Bodies; Keratins; Liver; Liver Diseases; Liver Neoplasms

Topics: Autoantibodies; Autoimmune Diseases; Biomarkers; Cytoskeleton; Humans; Infections; Keratins; Liver Diseases; Muscle, Smooth

Topics: Adrenal Cortex Hormones; Animals; Antigen-Presenting Cells; Antigens, Surface; Autoimmune Diseases; Cells, Cultured; Complement System Proteins; Cytoplasmic Granules; Epidermal Cells; Epidermis; Epitopes; Humans; Immunosuppressive Agents; Keratins; Langerhans Cells; Major Histocompatibility Complex; Mice; Pemphigus; Research

Topics: Actins; Animals; Autoantibodies; Autoantigens; Autoimmune Diseases; Cytoskeleton; Fluorescent Antibody Technique; Glial Fibrillary Acidic Protein; Humans; Immunoassay; Intermediate Filament Proteins; Keratins; Mice; Microtubules; Tubulin; Vimentin

Alopecia areata (AA) is considered a highly heritable, T-cell-mediated autoimmune disease of the hair follicle. However, no convincing susceptibility gene has yet been pinpointed in the major histocompatibility complex (MHC), a genome region known to be associated with AA as compared to other regions.. We engineered mice carrying AA risk allele identified by haplotype sequencing for the MHC region using allele-specific genome editing with the CRISPR/Cas9 system. Finally, we performed functional evaluations in the mice and AA patients with and without the risk allele.. We identified a variant (rs142986308, p.Arg587Trp) in the coiled-coil alpha-helical rod protein 1 (CCHCR1) gene as the only non-synonymous variant in the AA risk haplotype. Furthermore, mice engineered to carry the risk allele displayed a hair loss phenotype. Transcriptomics further identified CCHCR1 as a novel component interacting with hair cortex keratin in hair shafts. Both, these alopecic mice and AA patients with the risk allele displayed morphologically impaired hair and comparable differential expression of hair-related genes, including hair keratin and keratin-associated proteins (KRTAPs).. Our results implicate CCHCR1 with the risk allele in a previously unidentified subtype of AA based on aberrant keratinization in addition to autoimmune events.. This work was supported by JSPS KAKENHI (JP16K10177) and the NIHR UCLH Biomedical Research center (BRC84/CN/SB/5984).

Topics: Alleles; Alopecia Areata; Animals; Autoimmune Diseases; Carrier Proteins; Disease Models, Animal; Genetic Predisposition to Disease; Genome; Hair; Hair Follicle; Haplotypes; Humans; Intracellular Signaling Peptides and Proteins; Keratins; Keratins, Hair-Specific; Major Histocompatibility Complex; Mice; T-Lymphocytes

Topics: Animals; Autoimmune Diseases; Autoimmunity; Humans; Inflammation; Inflammation Mediators; Keratins; Signal Transduction; Skin; Skin Diseases

Alopecia areata (AA) has been recently shown to also include T-helper cell type 2/IL-23 activation, in addition to T-helper cell type 1/IFN-skewing. The success of Jak inhibition together with IL-4Rα antagonism and limited response to IL-17A and PDE4 (protein) inhibition in AA are increasing our understanding of the complex immune interplay in AA. Trials testing targeted therapeutics are needed to further elucidate the pathogenic contribution of various cytokines.

Topics: Alopecia Areata; Autoimmune Diseases; Cytokines; Gene Expression; Humans; Keratins; Molecular Targeted Therapy; Transcriptome

Dry eye is commonly associated with autoimmune diseases such as Sjögren's syndrome (SS), in which exocrinopathy of the lacrimal gland leads to aqueous tear deficiency and keratoconjunctivitis sicca (KCS). KCS is among the most common and debilitating clinical manifestations of SS that is often recalcitrant to therapy. We established mice deficient in the autoimmune regulator (Aire) gene as a model for autoimmune-mediated aqueous-deficient dry eye. In Aire-deficient mice, CD4+ T cells represent the main effector cells and local signaling via the interleukin-1 (IL-1/IL-1R1) pathway provides an essential link between autoreactive CD4+ T cells and ocular surface disease. In the current study, we evaluated the efficacy of topical administration of IL-1R1 antagonist (IL-1RA) anakinra in alleviating ocular surface damage resulting from aqueous-deficient dry eye in the setting of autoimmune disease.. We compared the effect of commercially available IL-1R1 antagonist, anakinra (50 μg/mL concentration) to that of carboxymethylcellulose (CMC) vehicle control as a treatment for dry eye. Age-matched, Aire-deficient mice were treated three times daily with anakinra or CMC vehicle for 14 days using side-by-side (n = 4 mice/group) and paired-eye (n = 5) comparisons. We assessed (1) ocular surface damage with lissamine green staining; (2) tear secretion with wetting of phenol-red threads; (3) goblet cell (GC) mucin glycosylation with lectin histochemistry; (4) immune cell infiltration using anti-F4/80, CD11c, and CD4 T cell antibodies; and (5) gene expression of cornified envelope protein, Small Proline-Rich Protein-1B (SPRR1B) with real-time quantitative polymerase chain reaction.. Aire-deficient mice treated with anakinra experienced significant improvements in ocular surface integrity and tear secretion. After 7 days of treatment, lissamine green staining decreased in eyes treated with anakinra compared to an equivalent increase in staining following treatment with CMC vehicle alone. By day 14, lissamine green staining in anakinra-treated eyes remained stable while eyes treated with CMC vehicle continued to worsen. Accordingly, there was a progressive decline in tear secretion in eyes treated with the CMC vehicle compared to a progressive increase in the anakinra-treated eyes over the 2-week treatment period. Aberrant acidification of GC mucins and pathological keratinization of the ocular surface were significantly reduced in anakinra-treated eyes. Significantly fewer Maackia amurensis leukoagglutinin positive goblet cells were noted in the conjunctiva of anakinra-treated eyes with a corresponding decrease in the expression of the pathological keratinization marker, SPRR1B. Finally, there was a downward trend in the infiltration of each immune cell type following anakinra treatment, but the cell counts compared to eyes treated with the vehicle alone were not significantly different.. IL-1R antagonist, anakinra, demonstrates therapeutic benefits as a topical treatment for aqueous-deficient dry eye in a spontaneous mouse model of autoimmune KCS that mimics the clinical characteristics of SS. Targeting the IL-1/IL-1R1 signaling pathway through topical administration of IL-1RA may provide a novel option to improve ocular surface integrity, increase tear secretion, and restore the normal glycosylation pattern of GC mucins in patients with SS.

Topics: Administration, Topical; Animals; Aqueous Humor; Autoimmune Diseases; Biomarkers; Dry Eye Syndromes; Gene Expression Regulation; Glycosylation; Goblet Cells; Interleukin 1 Receptor Antagonist Protein; Keratins; Leukocytes; Mice; Mice, Knockout; Mucins; Tears

Type 1 autoimmune pancreatitis (AIP) is histologically characterized by dense lymphoplasmacytic infiltration and marked storiform fibrosis, manifestations associated with pancreatic ducts. Such periductal lymphocyte recruitment is thought to be elicited by dysregulation of mechanisms governing physiological lymphocyte homing. The present study was undertaken to determine whether vascular addressins including peripheral lymph node addressin and mucosal addressin cell adhesion molecule 1 (MAdCAM-1) play a role in type 1 AIP histogenesis.. Tissue sections of type 1 AIP and tumor-associated non-AIP chronic pancreatitis, as well as normal pancreas, were subjected to immunohistochemical analysis using vascular addressin-related antibodies.. The number of periductal mouse endothelial cell antigen 79-positive high endothelial venule (HEV)-like vessels was increased in type 1 AIP relative to that seen in non-AIP chronic pancreatitis, whereas the number of MAdCAM-1-positive HEV-like vessels did not differ between the 2 conditions. Mouse endothelial cell antigen 79 antigens are expressed on duct-forming epithelial cells not only in pancreas but also in salivary glands, which often harbor extrapancreatic lesions in type 1 AIP.. Type 1 AIP can be characterized by periductal induction of MECA-79-positive HEV-like vessels. MECA-79-positive 6-sulfo sialyl Lewis X-related carbohydrate antigens expressed on duct-forming epithelial cells could be associated with type 1 AIP pathogenesis.

Topics: Antigens, CD34; Antigens, Surface; Autoimmune Diseases; Biomarkers; Cell Adhesion Molecules; Humans; Immunoglobulin G; Immunoglobulins; Immunohistochemistry; Keratins; Lymphatic Vessels; Membrane Proteins; Mucoproteins; Pancreatic Ducts; Pancreatitis

To explore the biological significance of the lymphatics in the autoimmune process, the thymus from non-obese diabetic (NOD) mice was evaluated by histochemistry and western blot analysis. Thymic lymphatic endothelial cells showed suggestive expression patterns of the functional molecules lymphatic vascular endothelial hyaluronan receptor (LYVE)-1, CCL21, CD31 and podoplanin. With increasing age, the expression of CCL21 was reduced in the medullary epithelial cells and lymphatics. Of note, LYVE-1-expressing lymphatics, filled with a cluster of thymocytes, increased in number and size and extended from the corticomedullary boundary into the medulla as the insulitis progressed. The development of lymphatic compartments was occasionally accompanied by a regional disappearance between the cortex and medulla. The CD4- and CD8-positive T cells frequently penetrated through the slender lymphatic walls. The epithelial reticular cell layer lining the perivascular spaces was extensively stained with cytokeratin, but the expression of cytokeratin showed an age-dependent decrease. These findings indicate that the occurrence of LYVE-1-expressing lymphatic compartments and the alteration of CCL21 expression in the lymphatics may be involved in defective thymocyte differentiation and migration, and play a significant role in insulitic and diabetic processes.

Topics: Aging; Animals; Autoimmune Diseases; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Chemokine CCL21; Chemokines, CC; Diabetes Mellitus; Disease Models, Animal; Epithelial Cells; Glycoproteins; Immunohistochemistry; Islets of Langerhans; Keratins; Lymphatic Vessels; Lymphocyte Activation; Membrane Glycoproteins; Membrane Transport Proteins; Mice; Mice, Inbred NOD; Platelet Endothelial Cell Adhesion Molecule-1; T-Lymphocytes; Thymus Gland

Peptides derived from amino acid sequence 60-80 of HLA-B27 (B27PA, aa 60-72 and B2702PA, aa 60-80) mimic cytokeratin and are able to induce in vitro proliferation of human peripheral blood lymphocytes as well as arthritis in Lewis rats. Here we show that the pathogenic epitope recognized by autoaggressive rat T cells is located at the N-terminus of the sequence, between aa 60 and 72. A C-terminally elongated 25mer peptide (B2702.60-84) showed increased pathogenicity, indicating either a second arthritogenic epitope or an immunomodulatory region within this peptide. B2702.60-84 has been described to inhibit murine and human CD8 + cytotoxic T cells (CTL) and was even successfully used for the treatment of allograft rejection. In addition to pathogenicity we have investigated the immunomodulatory effect of peptide B2702.60-84 in our rat model of experimental autoimmune uveitis (EAU), induced with retinal S-Antigen peptide PDSAg. We found that disease exacerbated following coimmunization of PDSAg with B2702.60-84. In vitro, the B27-peptide enhanced the proliferation of CD4+ T cell lines specific for retinal autoantigen peptides during coincubation of B2702.60-84 with the respective antigen. Oral tolerance induction, an effective mechanism to prevent uveitis in Lewis rats, is abrogated by cofeeding peptide B2702.60-84 with the tolerogen PDSAg. In rat EAU, naturally occurring regulatory T cells and orally induced gamma deltaTCR+ suppressor cells are CD8+ which might be impeded by peptide B2702.60-84. As a consequence of their abrogated suppressive capacity disease was exacerbated. We propose a similar role of HLA-B27 in man: disturbing the mechanisms down-regulating self-responses might lead to autoimmune diseases. This could explain the high association of HLA-B27 with a variety of autoimmune diseases targeting different organs or tissues.

Topics: Amino Acid Sequence; Animals; Arthritis; Autoimmune Diseases; Cell Proliferation; Disease Models, Animal; Female; HLA-B27 Antigen; Immune Tolerance; Keratins; Male; Molecular Sequence Data; Peptide Fragments; Rats; Rats, Inbred Lew; T-Lymphocytes; Uveitis

TCR transgenic mice that express a peptide antigen in keratinocytes develop a lethal CD8 T cell-dependent autoimmune disease. We employed an adoptive transfer system to understand this disease and show that transfer of low numbers of naive CD8 T cells into peptide transgenic mice caused chronic skin disease. The antigen-presenting cell that initiated this response was the epidermal Langerhans cell. Naive CD8 T cells proliferated extensively, migrated to tissues, developed effector function, and were capable of making a recall response. These features are very different from the abortive activation of CD8 T cells that occurred in response to the same antigen presented by APC from other tissues. Furthermore, tolerance was dominant when the antigen was presented by both Langerhans cells and other APC. These data suggest that Langerhans cells do not have tolerogenic properties in the steady state.

Topics: Adoptive Transfer; Animals; Antigen Presentation; Autoantigens; Autoimmune Diseases; CD8-Positive T-Lymphocytes; Cell Movement; Disease Models, Animal; Humans; Immune Tolerance; Keratin-14; Keratins; Langerhans Cells; Lymphocyte Activation; Mice; Mice, Transgenic; Ovalbumin; Promoter Regions, Genetic; Skin Diseases

Using a previously described human keratin 14 (K14) promoter, we created mice expressing a peptide Ag (OVAp) in epithelial cells of the skin, tongue, esophagus, and thymus. Double transgenic mice that also express a TCR specific for this Ag (OT-I) showed evidence for Ag-driven receptor editing in the thymus. Surprisingly, such mice exhibited a severe autoimmune disease. In this work we describe the features of this disease and demonstrate that it is dependent on CD8 T cells. Consistent with the Ag expression pattern dictated by the human K14 promoter, an inflammatory infiltrate was observed in skin and esophagus and around bile ducts of the liver. We also observed a high level of TNF-alpha in the serum. Given that Ag expression in the thymus induced development of T cells with dual TCR reactivity, and that dual-reactive cells have been suggested to have autoimmune potential, we tested whether they were a causal factor in the disease observed here. We found that OT-I/K14-OVAp animals on a recombinase-activating gene-deficient background still suffered from disease. In addition, OT-I animals expressing OVA broadly in all tissues under a different promoter did not experience disease, despite having a similar number of dual-specific T cells. Thus, in this model it would appear that dual-reactive T cells do not underlie autoimmune pathology. Finally, we extended these observations to a second transgenic system involving 2C TCR-transgenic animals expressing the SIY peptide Ag with the hK14 promoter. We discuss the potential relationship between autoimmunity and self-Ags that are expressed in stratified epithelium.

Topics: Animals; Antigens; Autoimmune Diseases; CD8-Positive T-Lymphocytes; Egg Proteins; Epithelial Cells; Gene Expression; Genes, T-Cell Receptor; Humans; Keratin-14; Keratins; Mice; Mice, Inbred C57BL; Mice, Knockout; Mice, Transgenic; Ovalbumin; Peptide Fragments; Promoter Regions, Genetic; Receptors, Antigen, T-Cell, alpha-beta

The analysis of the antibody repertoire of patients with giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) might identify target antigens of the autoimmune response with potential relevance to our understanding of the pathogenesis of the disease and to the development of serodiagnostic tests. To detect such antigens, we screened a cDNA library derived from normal human testis for antigens reacting with IgG antibodies in the 1 : 250 diluted sera of three patients with untreated GCA using SEREX, the serological identification of antigens by recombinant cDNA expression cloning. Of 100 000 clones screened with each serum, six, 28 and six clones, respectively, were positive, representing a total of 33 different antigens. Most of the antigens reacted only with the serum used for identification and/or at a similar frequency with normal control sera. However, lamin C and the nuclear antigen of 14 kD reacted specifically with 32% of GCA/PMR, but with none of the control sera, while human cytokeratin 15, mitochondrial cytochrome oxidase subunit II, and a new gene product were detected preferentially, but not exclusively by sera from GCA/PMR patients. We conclude that patients with GCA/PMR develop antibodies against a broad spectrum of human autoantigens. Antibodies against human lamin C, the nuclear autoantigen of 14 kD as well as human cytokeratin 15, mitochondrial cytochrome oxidase subunit II and the product of a new gene should be investigated further to determine their value as tools for the diagnosis and/or the definition of clinical subgroups of patients with GCA/PMR.

Topics: Adult; Aged; Aged, 80 and over; Antibody Specificity; Autoantibodies; Autoantigens; Autoimmune Diseases; B-Lymphocytes; Cytoskeleton; DNA, Complementary; Electron Transport Complex IV; Female; Giant Cell Arteritis; Humans; Immunoglobulin G; Keratins; Lamin Type A; Lamins; Male; Middle Aged; Nuclear Proteins; Polymyalgia Rheumatica; Protein Subunits; Testis

Histopathological changes of biopsied pancreata were examined in three diabetic patients with autoimmune chronic pancreatitis (ACP). We found intra- and periinsular mononuclear cell (MNC)-mainly CD8+ T cell-infiltration as well as MNC infiltration around the ductal cells. Islet beta cell volume decreased significantly. Some ductal cells expressed insulin and insulin promoter factor-1 concomitantly in the affected pancreas. These findings provide new insight toward understanding the pathological mechanisms of corticosteroid treatment-responsive diabetes associated with ACP.

Topics: Adrenal Cortex Hormones; Aged; Autoimmune Diseases; Biopsy; CD8-Positive T-Lymphocytes; Diabetes Complications; Diabetes Mellitus; HLA Antigens; Humans; Immunohistochemistry; Insulin; Islets of Langerhans; Keratins; Male; Middle Aged; Pancreatitis

To investigate whether antikeratin antibodies (AKA) could be useful in the differential diagnosis of patients with rheumatoid arthritis (RA) compared to patients with hepatitis C virus (HCV) associated polyarthritis, who are seropositive for rheumatoid factor (RF).. AKA were assayed in 3 different groups of patients; all were RF seropositive: Group 1: 25 patients with HCV associated polyarthralgia or arthritis. Group 2: 33 patients with RA. Group 3: 13 patients with autoimmune disorders other than RA. Fifteen healthy individuals served as controls.. AKA were detected in 20/33 patients with RA (60.6%) compared to only 2/25 patients (8%) with HCV associated arthritis (p < 0.0001). AKA were observed in 2/13 patients of Group 3 (15.3%). These results were also statistically different from those of patients with RA (p = 0.008). AKA were not found in the sera of the healthy controls.. AKA is a useful marker to differentiate patients with RA from those with hepatitis C arthritis.

Topics: Adult; Aged; Antibodies; Arthritis; Arthritis, Rheumatoid; Autoimmune Diseases; Diagnosis, Differential; Female; Hepatitis C; Humans; Immunologic Tests; Keratins; Male; Middle Aged

Our objective was to investigate the presence of a B and T cell immune response directed against the glycine-rich cell wall protein (GRP) in patients with different autoimmune disorders and with food allergy. GRP is an ubiquitous food protein that has high homology with cytokeratins and other self proteins [Epstein-Barr virus nuclear antigen-1 (EBNA-I), heterogeneous nuclear ribonucleoprotein, fibrillar collagen] which are common targets in autoimmune disorders. A peptide (GGYGDGGAHGGGYGG) derived from GRP was used to screen human sera in direct and competitive ELISA assay. Anti-GRP-specific IgG were analyzed for their ability to cross-react with autoantigens. The intracellular cytokine profiles of the peptide-specific T cell clones obtained from representative patients have been studied. BALB/c mice were immunized with the peptide coupled to the carrier protein keyhole limpet hemocyanin (KLH). Serum IgG antibodies directed against the GRP peptide were detected in several autoimmune disorders and in food allergic patients, and were able to cross-react with autoantigens including keratin, collagen and EBNA-I. Twenty-five T cell clones showed a specific proliferative response to the GRP peptide and were of the T(h)0 phenotype. Eight of the 10 BALB/c mice immunized with the peptide coupled to KLH developed an autoimmune response. Our data suggest that phylogenetically highly conserved epitopes in plants, viruses and humans may be responsible for an autoimmune response in susceptible individuals. They also indicate that the antigen spreading of a particular sequence among apparently divergent proteins may participate to initiate or amplify an immune response.

Topics: Amino Acid Sequence; Animals; Antigens, Surface; Autoantigens; Autoimmune Diseases; Cell Division; Collagen; Cross Reactions; Cytokines; Enzyme-Linked Immunosorbent Assay; Epitopes; Epstein-Barr Virus Nuclear Antigens; Flow Cytometry; Food Hypersensitivity; Hemocyanins; Humans; Immunoglobulin G; Keratins; Mice; Mice, Inbred BALB C; Molecular Sequence Data; Plant Proteins; T-Lymphocytes, Helper-Inducer

Topics: Animals; Antigen-Antibody Reactions; Autoantibodies; Autoantigens; Autoimmune Diseases; Cadherins; Cell Adhesion; Cell Adhesion Molecules; Cytoskeletal Proteins; Desmoglein 3; Desmoplakins; Desmosomes; Humans; Keratins; Membrane Proteins; Paraneoplastic Syndromes; Pemphigus; Plakins; Protein Precursors

Topics: Arthritis, Rheumatoid; Autoantibodies; Autoimmune Diseases; Biomarkers; Filaggrin Proteins; Humans; Intermediate Filament Proteins; Keratins; Rheumatoid Factor

Agarose-encapsulated nuclear matrix preparations of the lower eukaryote Physarum polycephalum and the mammalian renal epithelial LLC-PK1 cell line were analyzed after various experimental protocols with respect to the protein composition. The effect of the mode of deproteinization (2 M NaCl, 0.25 M ammonium sulfate or 25 mM lithium diiodosalicylate), presence of 2-mercaptoethanol, Ca2+, Cu2+, chelating agents, the sequence of protein extraction and nuclease digestion, the use of RNase, the temperature at which the experimental manipulations were performed and the use of hypotonic or isotonic conditions was investigated. No significant differences in the final nuclear matrix composition could be observed, regardless of the experimental procedure applied. In Physarum, the major nuclear matrix proteins range over 12-70 kDa with prominent bands at 24, 31, 37 and 45 kDa; the proteins of the matrix in LLC-PK1 cells extend predominantly over 40-80 kDa. Furthermore, no essential differences in the protein composition could be observed when type I and type II nuclear matrices from the highly differentiated LLC-PK1 cell line were compared. The same was found for analogous matrix preparations of Physarum. Therefore, in both systems a distinction between type I/II matrix is questionable. Immunoblotting of the matrix preparations with a variety of antibodies against intermediate filament proteins and with antinuclear autoantibodies revealed the presence of intermediate filament proteins as components of the nuclear matrix. We conclude that the nuclear matrix represents a much more stable and reproducible structure than has been proposed so far, largely independent of changes in the preparation protocol.

Topics: Animals; Antigens, Nuclear; Autoimmune Diseases; Calcium; Cell Line; Copper; Humans; Keratins; Kidney; Nuclear Matrix; Nuclear Proteins; Physarum polycephalum; Swine

The MRL/Mp-lpr/lpr (MRL/l) mouse is an autoimmune model of spontaneous lupus erythematosus (LE), in addition to lupus nephritis. In order to better understand the mechanisms of photosensitivity in LE, in vitro photocytotoxicity was examined by using fibroblasts and keratinocytes cultured from MRL/l mice, control MRL/Mp- +/+ (MRL/n) mice, and normal BALB/c mice. A colorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and the acridine orange/ethidium bromide assay were used for determination of cytotoxicity. Fibroblasts cultured from newborn MRL/l mice showed higher susceptibility to single ultraviolet light B (UVB) light irradiation at a dose of 100-500 mJ than those from MRL/n, F1 hybrid of (MRL/l x MRL/n mice), and BALB/c mice. However, the susceptibility to UVB was not observed in young (1-month-old) and adult (4-month-old) MRL/l mice. UVA light irradiation was not cytotoxic. Keratinocytes cultured from MRL mice showed lower cytotoxicity to UVB irradiation than fibroblasts cultured. However, keratinocytes from newborn MRL/l mice showed higher cytotoxicity to 50 mJ UVB irradiation than cells from MRL/n mice. Syngeneic or allogeneic sera augmented UVB-induced cytotoxicity of fibroblasts cultured. UVB irradiation of spleen cells induced no significant difference of cytotoxicity between MRL/l and MRL/n mice. Based on the results of F1 hybrid of (MRL/l x MRL/n) mice, the susceptibility seemed to be associated with autoimmune traits and to be regulated by genetical background.

Topics: Animals; Animals, Newborn; Autoimmune Diseases; Cell Survival; Cells, Cultured; Dose-Response Relationship, Radiation; Epidermal Cells; Epidermis; Fibroblasts; Keratins; Mice; Mice, Inbred BALB C; Mice, Mutant Strains; Skin; Species Specificity; Ultraviolet Rays

Topics: Autoantibodies; Autoimmune Diseases; Enzyme-Linked Immunosorbent Assay; Humans; Keratins; Skin; Skin Diseases

Pemphigus foliaceus is an uncommon dermatologic disorder occurring in several species and has been reported in horses during the past decade. An ultrastructural analysis of affected skin of horses presenting to our clinics has revealed early cytopathologic features of pemphigus-like disease, some of which closely resemble pemphigus foliaceus in the human, calve, and guinea pig. Prior to complete acantholysis and bullae formation, the intercellular spaces enlarged, but intercellular bridges and desmosomes remained intact. A novel finding was presence of aggregates of electron dense granular material which were seen in intercellular spaces of the epidermal basal cell layer, and may represent antigen-autoantibody complexed material or deranged cement substances. Other changes preceding acantholysis consisted of mild dyskeratosis, reduction of peripheral tonofilaments, enlargement of rough endoplasmic reticula, cytoplasmic vacuolization, and mitochondrial damage in epidermal cells. In more severe lesions where bullae were present and acantholysis was observed, bacterial invasion and leucocytic infiltration were evident in all epidermal layers, and corneal cells displayed cytoplasmic vacuolization and retention of nuclei. Basal cells remained intact, though intercellular spaces were enlarged on apical and lateral boundaries. The pathogenesis of this disease in the horse appeared morphologically similar to a pemphigus autoimmune disorder and its variants in other species, and morphologic evidence is provided to suggest that some cellular metabolic derangements may be concurrent with the extracellular events or cell peripheral changes that precede acantholysis and bullae formation.

Topics: Animals; Autoimmune Diseases; Corneal Diseases; Dermatitis; Epidermal Cells; Female; Horse Diseases; Horses; Keratins; Male; Pemphigus

A major component of the thymic microenvironment is a network of thymic epithelial cells (TEC) which are able to express class II major histocompatibility complex products and to secrete thymic hormones. In the present investigation, we used a panel of anti-cytokeratin (CK) antibodies to establish distinct cytokeratin-defined TEC subsets. Four subpopulations were identified. One, in the cortex, is defined by anti-CK8 and anti-CK18 monoclonal antibodies (MAb). The other three subsets are medullary, two minor ones respectively reactive with anti-CK19 and KL1 monoclonal antibodies (the latter being specific for CK3 and 10), and a major one characterized by negative reaction with the above-mentioned MAb but strongly positive after labeling with a polyclonal (and polyspecific) anti-keratin immunoserum. Ontogenetic studies revealed that the CK8+/18+ TEC subset is the first to be detected in fetal life. Moreover, the numbers of CK3/10+ cells and CK19+ cells decrease in aging normal mice, a phenomenon that seems to occur early in autoimmune mice. We also observed that these two medullary TEC subsets are sensitive to high-dose in vivo treatment with hydrocortisone, which stimulates a dramatic increase in CK3/10+ cells and a certain decrease in CK19+ cells. Our results indicate that a number of mouse TEC subsets can be distinguished by cytokeratin expression. Such a strategy can be applied to analyze TEC sensitivity to drugs and might also be useful to further understanding of differential TEC function regarding intrathymic T-cell differentiation.

Topics: Age Factors; Animals; Antibodies, Monoclonal; Atrophy; Autoimmune Diseases; Diabetes Mellitus, Experimental; Epithelium; Female; Fluorescent Antibody Technique; Hydrocortisone; Keratins; Male; Mice; Mice, Inbred Strains; Thymus Gland

The thymic epithelium, a major component of the thymic microenvironment, is a heterogeneous tissue bearing distinct monoclonal antibody-defined subsets. Among these, KL1+ cells represent a mouse medullary subpopulation characterized by high mol wt cytokeratin expression. Given the fact that thymic epithelial cells (TEC) express glucocorticoid receptors and that glucocorticoid hormones are known to modulate the expression of keratins, we decided to study the in vivo effects of hydrocortisone on KL1+ cells in normal and autoimmune mice. Within 24 h after a single injection of this steroid we observed a significant increase in the number of KL1+ cells. Interestingly, this effect was reversible and was no longer detected 7 days after treatment. Parallel studies analyzing the effects of hydrocortisone on the secretion of thymulin, a chemically defined thymic hormone revealed a transient decrease in serum levels of this hormone, but with different kinetics than the effects on KL1+ cells. Ontogenetic studies showed that the responsiveness of TEC to hydrocortisone, in terms of high mol wt cytokeratin expression, appeared late in fetal life and disappeared in aging animals. Importantly, aging, but also young adult, autoimmune mice were not responsive. In vitro experiments using a mouse TEC line confirmed the data observed in vivo demonstrating that the increase in KL1+ cells is a direct effect of hydrocortisone on TEC. The bulk of the data presently reported demonstrates that glucocorticoid hormone can act on TEC modulating the expression of both secretory and cytoskeletal protein families.

Topics: Aging; Animals; Atrophy; Autoimmune Diseases; Cell Count; Dose-Response Relationship, Drug; Epithelium; Hydrocortisone; Immunoblotting; Keratins; Kinetics; Male; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Inbred NZB; Molecular Weight; Thymic Factor, Circulating; Thymus Gland

The so-called lymphofollicular hyperplasia, which is caused by the occurrence of hyperplastic lymph follicles within the organ, is constantly associated with autoimmune diseases (e.g., myasthenia gravis) and in rare instances with malignant tumors. The architecture of lymphofollicular hyperplasia was studied immunohistochemically using antibodies against epithelial, vascular, lymphocytic, and histiocytic antigens. There is evidence, that the configuration, microtopography, cellular composition, and immunohistological findings of the lymph follicles with germinal centers in the myasthenic thymus are essentially the same as in those occurring in lymph nodes and in other lymphatic tissue. Furthermore it could be shown that the follicles originate in the interlobular septal space and displace the thymic parenchyma by extension.

Topics: Adolescent; Adult; Autoimmune Diseases; Child; Child, Preschool; Epithelium; Humans; Immunoenzyme Techniques; Infant; Keratins; Myasthenia Gravis; Thymectomy; Thymus Gland; Thymus Hyperplasia

IgG anti-keratin-filament autoantibodies occur in all human sera and reach high titres in the sera of patients with various cutaneous and non-cutaneous diseases. At indirect immunofluorescence, these autoantibodies may, depending on their titre, appear as 'upper-cytoplasmic' antibodies or 'stratum-corneum' antibodies. In vitro, IgG anti-keratin-filament autoantibodies significantly enhance (as opsonins) the phagocytosis of keratin-filament aggregates by human monocytes and polymorphonuclear leucocytes. They may therefore, also in vivo, play a role in the removal of insoluble extracellular keratin-filament aggregates generated by necrotic or apoptotic cell death. Keratin (Civatte) bodies and deposits of localized cutaneous amyloid are examples of such keratin-filament aggregates that are found in various skin diseases but are also regularly present in large amounts in normal human skin. IgM anti-keratin-filament autoantibodies, which may, at indirect immunofluorescence, appear as 'general cytoplasmic' antibodies, also occur in all human sera and reach high titres in the sera of patients with various diseases. The regular presence of IgM in keratin bodies or deposits of localized cutaneous amyloid therefore probably represents the binding of IgM anti-keratin-filament autoantibodies to their respective antigens. To what extent these in vivo-bound autoantibodies prevent any further damaging reaction by the immune system in response to the liberation of keratin-filament autoantigen is as yet unclear.

Topics: Amyloid; Autoantibodies; Autoimmune Diseases; Humans; Immunoglobulins; Keratins; Opsonin Proteins; Phagocytosis; Skin Diseases

Pemphigus is a human disease that causes extensive blistering of the skin. This blistering is related to a loss of epidermal cell cohesion and is accompanied by circulating autoantibodies that stain epidermal cell surfaces, as shown by immunofluorescence microscopy. One of the major components involved in epidermal cell cohesion is the desmosome. The pathological changes that accompany pemphigus led us to determine whether the autoantibodies are specific for desmosomes. Incubation of cultured mouse keratinocytes in medium containing pemphigus antiserum leads to cell separation at cell-cell contact sites, which possess desmosomes. Tissue sections of mouse skin processed for indirect immunofluorescence, using pemphigus antiserum or a rabbit antiserum directed against components of desmosomes, show similar punctate cell-surface staining patterns within the epidermis. Cultured mouse keratinocytes possessing well-defined intermediate filament bundles (tonofilaments) and desmosomes were processed for double indirect immunofluorescence, using a monoclonal antibody directed against mouse skin keratin and either pemphigus antiserum or the desmosome antiserum. The keratinocytes exhibit a complex system of keratin-containing tonofilaments. Tonofilaments in contacting cells are separated by thin dark bands at the cell surface, which correspond precisely to desmosomal plaques seen by phase-contrast microscopy. These bands specifically stain with both pemphigus antiserum and the desmosome antiserum. Double indirect immunofluorescence of the cultured mouse keratinocytes, using pemphigus antiserum and the desmosome antiserum, reveals that the pemphigus autoantibodies stain the same areas of cell-cell contact as the desmosome antibodies. Our evidence supports the idea that pemphigus blisters form, at least in part, from a specific antibody-induced disruption of desmosomes in the epidermis.

Topics: Animals; Autoantibodies; Autoimmune Diseases; Cells, Cultured; Desmosomes; Epidermis; Humans; Keratins; Mice; Pemphigus

Antiperinuclear factor (APF) was detected in 7 out of 38 patients with autoimmune liver disease (AILD) and in 7 out of 83 patients with non-autoimmune liver disease (NAILD). Anti-keratin antibodies were found in 2 out of 18 patients with AILD and in 3 out of 32 patients with NAILD. Neither APF nor antikeratin antibody was significantly more frequent in AILD than in NAILD. The incidence of APF was shown to be greater (p less than 0.02) in patients with rheumatoid factor (RF) and/or antinuclear antibody. This supports the hypothesis that APF is connected with RF rather than with rheumatoid arthritis, although the presence of APF is evidence towards the diagnosis of rheumatoid arthritis.

Topics: Adult; Aged; Antibodies, Antinuclear; Autoantibodies; Autoimmune Diseases; Female; Hepatitis; Humans; Keratins; Liver Diseases; Male; Middle Aged

Topics: Adolescent; Adult; Antigen-Antibody Reactions; Antigens; Autoantibodies; Autoimmune Diseases; Colitis, Ulcerative; Epithelial Cells; Epithelium; Female; Fluorescent Antibody Technique; Humans; Keratins; Male; Multiple Sclerosis; Myasthenia Gravis; Rheumatic Fever; Skin; Thymus Gland