concanavalin-a and Glomerulonephritis

Glomerular diseases are leading causes of end-stage renal diseases worldwide. They are considered to be consequences of injury primarily to the three types of glomerular cells. Differential diagnosis typically relies on invasive biopsy findings. We expected that injuries of different glomerular cells would cause different changes in urinary proteome. The goal of this study was to identify differential urinary proteins distinguishing between injuries of different glomerular cells before significant histopathologic changes. Adriamycin nephropathy and Thy1.1 glomerulonephritis were employed as models with different primary impaired cells. ConA-enriched urinary glycoproteome on day3 were profiled by gel-free shotgun tandem mass spectrometry, and compared with self-healthy controls to identify differential urinary proteins for each model. By comparing the changes of the differential proteins between these two models, we identified 39 proteins with different directions of changes, which may potentially be useful in differentiation; and 7 proteins with the same direction of changes, which may be potential indicators of early renal damage. These differential proteins were of several origins: plasma proteins, proteins with urine or kidney specificity, proteins without tissue-specificity (mainly inflammatory mediators) etc. Our results may help better understand the effects of injuries of different glomerular cells at the initial stage, and lead to the discovery of novel early diagnostic markers for human focal segmental glomerulosclerosis (FSGS) and mesangioproliferative glomerulonephritis (MsPGN) which have the same primary impaired cells with adriamycin nephropathy and Thy1.1 glomerulonephritis, respectively.

Topics: Animals; Biomarkers; Concanavalin A; Diagnosis, Differential; Disease Models, Animal; Doxorubicin; Glomerulonephritis; Glycoproteins; Male; Proteome; Rats; Rats, Sprague-Dawley; Tandem Mass Spectrometry; Thy-1 Antigens

Blast transformation of peripheral blood lymphocytes stimulated with phytohemagglutinin and concanavalin A was studied in children with pyelonephritis and glomerulonephritis. Activity of natural killer cells from children with pyelonephritis was estimated before and after treatment with 50% autologous plasma. The autologous plasma modulated blast transformation of lymphocytes and activity of natural killer cells, which depended on the stage of diseases.

Topics: Adolescent; Child; Child, Preschool; Concanavalin A; Glomerulonephritis; Humans; Immune Tolerance; Immunotherapy; K562 Cells; Killer Cells, Natural; Lymphocyte Activation; Lymphocytes; Phytohemagglutinins; Pyelonephritis

We studied the role of the C5b-9 membrane attack complex in two models of inflammatory glomerulonephritis (GN) initiated by acute glomerular endothelial injury in Piebold-viral-Glaxo (PVG) complement-sufficient rats (C+), C6-deficient rats (C6-), and rats systematically depleted of complement with cobra venom factor (CVF). GN was induced by performing a left nephrectomy and selectively perfusing the right kidney with either 1) the lectin concanavalin A (Con A) followed by complement-fixing anti-Con A (Con A GN) or 2) purified complement-fixing goat anti-rat glomerular endothelial cell (GEN) antibody [immune-mediated thrombotic microangiopathy (ITM)]. Comparable levels of GEN apoptosis were detected in C+ animals in both models. CVF administration reduced GEN apoptosis by 10- to 12-fold. GEN apoptosis was C5b-9 dependent because PVG C6- rats were protected from GEN loss. Furthermore, functional inhibition of the cell surface complement regulatory protein CD59 by renal perfusion with anti-CD59 antibody in ITM resulted in a 3.5-fold increase in GEN apoptosis. Last, in Con A GN, abrogation of GEN apoptosis preserved endothelial integrity and renal function. This study demonstrates the specific role of C5b-9 in the induction of GEN apoptosis in experimental inflammatory GN, a finding with implications for diseases associated with the presence of antiendothelial cell antibodies.

Topics: Animals; Apoptosis; Complement C6; Complement Membrane Attack Complex; Concanavalin A; Disease Models, Animal; Endothelium; Glomerulonephritis; Kidney Glomerulus; Male; Rats; Thrombosis

Neutrophils (PMNs) and their toxic contents can injure glomeruli, but to date their fate in glomerulonephritis has been unknown. We studied glomerulonephritis induced in rats by formation of concanavalin A (Con A)/anti-Con A immune complexes on glomerular endothelial cells. PMN infiltration, which was almost exclusively confined to the lumen of glomerular capillaries, was transient, peaking at 4 hours, with only 9.0 +/- 4.1% (mean +/- SEM) of the maximum remaining at 24 hours. There was clear evidence of PMN apoptosis leading to phagocytosis in situ by intraluminal macrophages. However, the kinetics of leukocyte infiltration and PMN apoptosis, the preferential location at 24 hours of apoptotic PMNs within occluded capillary loops, and tracking of radiolabeled PMNs all indicated that in situ phagocytic clearance after apoptosis was the fate of a minority of PMNs, amounting to no more than one-fifth of the peak infiltrating load. Instead, the majority of infiltrating PMNs (72.9 +/- 3.1%) had emigrated from inflamed glomeruli by 24 hours, apparently returning to the circulation. We conclude that PMN emigration from inflamed glomeruli is a hitherto unrecognized mechanism for regulation of PMN-mediated glomerular injury.

Topics: Animals; Apoptosis; Capillaries; Cell Movement; Concanavalin A; Glomerulonephritis; Indium Radioisotopes; Infusions, Intravenous; Kidney Glomerulus; Lymph Nodes; Macrophages; Male; Neutrophils; Phagocytosis; Rats; Rats, Sprague-Dawley; Time Factors

P-selectin is one of the key early mediators of leukocyte adhesion in inflammatory conditions. This report examines the role of P-selectin in a neutrophil- and platelet-mediated model of glomerulonephritis (the concanavalin A [con A] model). The administration of neutralizing anti-P-selectin antibody (PB 1.3) reduced the platelet influx at 10 min (P < 0.05) and was associated with a 60% reduction in the neutrophil infiltrate and a 50% reduction in the number of oxidant-producing cells at 3 h within glomeruli. No effect on glomerular monocyte-macrophage accumulation was observed, and proteinuria was reduced by 20% but did not reach significance. It is concluded that P-selectin plays an important role in mediating the neutrophil and platelet accumulation in this model and likely has a role in mediating the glomerular injury.

Topics: Animals; Antibodies, Monoclonal; Blood Platelets; Cell Adhesion; Chemotaxis, Leukocyte; Complement C3; Concanavalin A; Endothelium, Vascular; Glomerulonephritis; Immune Complex Diseases; Immunoglobulin G; Infusions, Intra-Arterial; Kidney Glomerulus; Male; Neutrophils; P-Selectin; Platelet Adhesiveness; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Renal Artery

Complement is a major mediator of tissue injury in several types of glomerulonephritis. However, no therapeutic agents that inhibit complement activation are available for human use. sCR1 (TP10, BRL 55736) is a recombinant, soluble human complement receptor 1 (CR1) molecule lacking transmembrane and cytoplasmic domains that inhibits C3 and C5 convertase activity by preferentially binding C4b and C3b. To test the efficacy of sCR1 on complement-mediated glomerulonephritis, rats were pretreated with sCR1 (60 mg/kg per day) before and during the induction of three models of complement-dependent glomerulonephritis (concanavalin A and antithymocyte serum models of proliferative glomerulonephritis, passive Heyman nephritis). Daily sCR1 and complement hemolytic activity levels were measured, and renal histology and urine protein excretion were examined. Mean serum sCR1 levels of 100 to 200 micrograms/mL were maintained with a reduction in complement hemolytic activity to less than 15% in most animals. In the antithymocyte serum model, sCR1-treated animals had significant reductions in mesangiolysis, glomerular platelet and macrophage infiltrates, and proteinuria at 48 h. In the concanavalin A model, sCR1 significantly reduced glomerular C3 and fibrin deposits, platelet infiltrates, and proteinuria at 48 h. In passive Heymann nephritis, proteinuria was also significantly reduced (199 +/- 8.5 versus 125 +/- 16 mg/day, P < 0.002) at 5 days. It was concluded that sCR1 significantly reduces both morphologic and functional consequences of several different types of complement-mediated glomerulonephritis and deserves evaluation as a potential therapeutic agent in complement-mediated immune glomerular disease in humans.

Topics: Animals; Antilymphocyte Serum; Complement System Proteins; Concanavalin A; Disease Models, Animal; Glomerulonephritis; Immunoglobulin G; Kidney Glomerulus; Male; Rats; Rats, Sprague-Dawley; Rats, Wistar; Receptors, Complement; Recombinant Proteins

Twelve Beagles were inoculated with concanavalin A, and after a mean ninefold increase in antibody titer, 1 mg of concanavalin A was infused into each renal artery of each dog to induce in situ immune complex glomerulonephritis. Starting 4 weeks after renal arterial infusion, 6 dogs were treated orally 3 times daily with 30 mg of 3-methyl-2 (3 pyridyl)-1-indolectanoic acid (CGS 12970)/kg of body weight, a thromboxane synthetase inhibitor, and 6 dogs (control group) received a gelatin capsule 3 times daily. Endogenous creatinine clearance and 24-hour urinary excretion of protein and thromboxane B2 were determined for each dog prior to renal arterial infusion, at the initiation of treatment and at 2, 4, 6, and 8 weeks after initiation of treatment. In addition, methyoxy-3H inulin clearance was determined at initiation of treatment and 4 and 8 weeks later. Renal specimens were examined histologically at the initiation of treatment and 4 and 8 weeks later. Glomerular mononuclear profiles/microns 3 were determined from at least 10 equatorially sectioned glomeruli from each dog. Paired t tests were used to compare mean values at the various time points to the respective mean baseline value and 2-sample t tests were used to evaluate differences between treatment groups. At the start of treatment (4 weeks after renal arterial infusion of concanavalin A), histologic evaluation of renal specimens revealed glomerular epithelial crescent formation, mononuclear cell proliferation, and infiltration of neutrophils. Mononuclear cell profiles and urinary excretion of protein and thromboxane B2 were significantly increased, but endogenous creatinine clearance values were unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Animals; Antibodies; Concanavalin A; Creatinine; Dog Diseases; Dogs; Glomerular Filtration Rate; Glomerulonephritis; Immune Complex Diseases; Kidney; Male; Proteinuria; Pyridines; Thromboxane B2; Thromboxane-A Synthase

Oestrogen is known to accelerate glomerulonephritis and autoantibody production in human and murine systemic lupus erythematosus (SLE). In this study we demonstrate that treatment of castrated autoimmune MRL +/+ mice with physiological doses of oestrogen results in enhanced immunoglobulin and autoantibody production as well as increased deposition of IgG in renal glomeruli. Accelerated development of glomerulonephritis was also evident from the increase of albuminuria. Interestingly, in contrast to these deteriorative effects of oestrogen on immune complex-mediated disease we now show that the lymphocytic infiltrations in the submandibular glands and perivascular lesions in the kidneys were significantly diminished after exposure to oestrogen. This remarkable impact of physiological oestrogen levels on the outcome of SLE in MRL +/+ mice is postulated to be the result of a differential effect on T and B cell-mediated immune responses.

Topics: Animals; Antibodies, Antinuclear; Autoimmunity; Castration; Concanavalin A; Estradiol; Glomerulonephritis; Hemoglobinuria; Immunoglobulins; Kidney; Lupus Erythematosus, Systemic; Male; Mice; Oxazolone; Rheumatoid Factor; Salivary Glands; Sialadenitis; Spleen; Vasculitis

To determine the role of thromboxane A2 in the pathogenesis of experimentally induced immune complex glomerulonephritis, 12 concanavalin A-immunized Beagles were infused with 1 mg of concanavalin A via each renal artery and treated twice daily for 8 days with either 30 mg of CGS 12970/kg, PO, a specific thromboxane synthetase inhibitor, or placebo. The effect of treatment was assessed by measuring endogenous creatinine clearance and urine protein and eicosanoid excretion, and by evaluating changes in glomerular morphometric characteristics. On postinfusion day 8, urine protein, thromboxane B2, and 11-dehydro-thromboxane B2 excretion, glomerular epithelial crescent formation, and glomerular cell proliferation in the CGS 12970-treated dogs were significantly decreased when compared with values in the placebo-treated group. Differences were not observed in endogenous creatinine clearance, urine prostaglandin E2 and 6-keto-prostaglandin F1 alpha excretion, or glomerular polymorphonuclear leukocyte infiltration between groups in this study. These findings suggest thromboxane A2 has a role in the development of immune complex glomerulonephritis and that thromboxane synthetase inhibition may be beneficial in attenuating some of the functional and histological changes associated with immune complex glomerulonephritis.

Topics: 6-Ketoprostaglandin F1 alpha; Animals; Concanavalin A; Dinoprostone; Disease Models, Animal; Dogs; Glomerular Filtration Rate; Glomerulonephritis; Immune Complex Diseases; Kidney; Kidney Glomerulus; Male; Pyridines; Thromboxane A2; Thromboxane B2; Thromboxane-A Synthase

The perfusion of polymeric or secretory IgA-Concanavalin A complexes into the aorta of rats led to a mannose-dependent binding of both IgA and lectin to the glomerular capillary wall, as shown by double immunolocalization experiments, by quantitative analysis of the amount of radiolabelled complexes bound per g of kidney, and by blocking experiments with the corresponding carbohydrate. Rats injected with amounts of those complexes as low as 500 micrograms developed, one hour later, a focal and segmental proliferative glomerulonephritis characterized by the deposition of injected complexes and of rat C3 and rat fibrin/fibrinogen in most glomeruli; focal thrombosis and small areas of necrosis in 10 to 15% of glomeruli, confined to the periphery of a single lobule of the tuft and segmental infiltration of these glomeruli by polymorphonuclear leucocytes and platelets. At the same time, many mesangial cells exhibited a hyperactive appearance, and red blood cells were noted in tubular lumens. In contrast, rats similarly injected with either monomeric IgA-ConA complexes, multimeric or secretory IgA-peanut agglutinin complexes or polymeric or monomeric IgA aggregates of comparable apparent molecular weight did not develop obvious glomerular lesions within one hour. The data indicate that performed polymeric IgA-ConA complexes can specifically bind to glomerular structures in vivo and trigger acute glomerular lesions locally, analogous to those observed in some glomerular diseases associated with a cryoglobulinaemia.

Topics: Acute Disease; Animals; Concanavalin A; Female; Fluorescent Antibody Technique; Glomerulonephritis; Immunoglobulin A; Kidney Glomerulus; Microscopy, Electron; Microscopy, Fluorescence; Polymers; Rats; Rats, Inbred Strains

Topics: Animals; Antigen-Antibody Complex; Concanavalin A; Female; Fluorescent Antibody Technique; Glomerulonephritis; Humans; Immunoglobulin A; Microscopy, Electron; Rats; Rats, Inbred Strains

Mechanisms for initiation of glomerular fibrin deposition were studied using renal tissue obtained from two patients with rapidly progressive, crescentic glomerulonephritis. Histological examination showed extensive glomerular monocyte infiltration and fibrin deposition in both patients. Sonicated cell suspensions of isolated glomeruli from these patients contained markedly augmented levels of procoagulant activity (PCA) compared with the levels found in normal glomeruli. This PCA was characterized as tissue factor by its functional dependence on Factors VII and V, independence of Factors VIII and XII, inhibition by concanavalin A and phospholipase C, and association with cell membranes. Its coagulant activity was also inhibited by a specific monoclonal anti-human tissue factor antibody. Tissue factor could be identified in glomeruli from these two patients by indirect immunofluorescence using this antibody. These studies implicate extrinsic pathway activation via tissue factor in intraglomerular deposition of fibrin in these patients. Activated monocytes, known to be a potent source of procoagulant activity and seen in large numbers within glomeruli from these patients, are a likely source of this tissue factor.

Topics: Adolescent; Aged; Blood Coagulation Disorders; Blood Coagulation Factors; Concanavalin A; Female; Glomerulonephritis; Humans; Kidney Cortex; Kidney Glomerulus; Male; Thromboplastin; Type C Phospholipases

Neutrophils (PMNs) mediate injury in experimental glomerulonephritis (GN) in part via the release of reactive oxygen species, particularly hydrogen peroxide (H2O2). Recent kidney perfusion studies demonstrate that H2O2 can cause glomerular injury by reaction with halides in the presence of the PMN cationic enzyme myeloperoxidase (MPO) to form oxidants which can oxidize and halogenate tissue. We sought evidence for participation of the MPO system in a model of PMN-mediated immune complex (IC) GN. A PMN-dependent model of GN was developed in rats by perfusing the renal artery with concanavalin A followed by anticoncanavalin A antibody. PMN depletion abolished glomerular PMN infiltration and significantly reduced proteinuria (35 +/- 7 mg/day vs. 113 +/- 10, P less than 0.001). Rats that received Na125I (5.0 microCi) three and six hours following disease induction had more 125I incorporation in glomeruli and GBM at 48 hours than similarly treated rats that were PMN depleted (1200 cpm vs. 88 cpm, P less than 0.01). Glomerular iodination could not be demonstrated in a PMN-independent model of nephrotoxic nephritis induced with noncomplement fixing anti-GBM antibody. These data indicate that this model of PMN-mediated IC GN is associated with activation of the MPO-H2O2-halide system, which may participate in mediating glomerular injury.

Topics: Animals; Capillaries; Complement C3; Concanavalin A; Glomerulonephritis; Halogens; Hydrogen Peroxide; Immune Complex Diseases; Immunoglobulin G; Iodine; Kidney Glomerulus; Leukocyte Count; Neutrophils; Peroxidase; Rats; Rats, Inbred Strains

Topics: Adolescent; Child; Concanavalin A; Glomerulonephritis; Humans; T-Lymphocytes

Cyclophosphamide is widely used to induce a remission of minimal-change nephropathy, but concerns have been raised about whether its effects on cellular immunity persist after treatment is discontinued. We studied functional and numerical measures of cellular immunity in children who had minimal-change nephropathy with frequent steroid-responsive relapses and were receiving cyclophosphamide (2.5 mg per kilogram of body weight per day for eight weeks). Sequential studies during such treatment showed that cyclophosphamide caused lymphopenia, particularly among T helper cells, resulting in a significant fall in the immunoregulatory (helper/suppressor) cell ratio. This change persisted 1 to 3 months after cyclophosphamide was discontinued, but measures of immune function reverted to normal after 6 to 12 months. Children with minimal-change nephropathy in long-term remission had no difference in T-cell subpopulations, lymphocyte responses to mitogens, or suppressor-cell function that could be attributed to the disease itself or to the previous use of cyclophosphamide.

Topics: Child; Concanavalin A; Cyclophosphamide; Glomerulonephritis; Humans; Lymphocyte Activation; Lymphocytes; Phytohemagglutinins; T-Lymphocytes, Helper-Inducer; T-Lymphocytes, Regulatory

Topics: Adolescent; Child; Child, Preschool; Chronic Disease; Concanavalin A; Glomerulonephritis; Humans; Lymphocyte Activation; Nephrotic Syndrome; Receptors, Fc; Rosette Formation; T-Lymphocytes, Regulatory

The response of lymphocytes to Concanavalin A (Con A) was measured in patients with the nephrotic syndrome due to minimal change nephropathy (11 patients), focal glomerulosclerosis (15 patients) and membranous nephropathy (21 patients); autologous serum was not used in these studies. There was a significant reduction in lymphocyte transformation in each group of patients compared to normal controls (p less than 0.01 for each group), but there was no significant difference between the individual groups of patients. Impaired lymphocyte transformation to Con A appears therefore to be a general feature of the nephrotic syndrome and is not exclusive to minimal change nephropathy. Measurements of suppressor cell function in 4 patients with minimal change nephropathy, 9 patients with focal glomerulosclerosis and 12 patients with membranous nephropathy were performed at the same time as the above studies. In each group suppressor cell function was decreased, indicating that the impaired lymphocyte response to Con A is not due to increased suppressor cell activity. These findings do not support the hypothesis that an abnormality of lymphocyte function peculiar to minimal change nephropathy is pathogenetic in that disease and not in other causes of the nephrotic syndrome; it seems more likely that the abnormalities described are secondary to the nephrotic state.

Topics: Adolescent; Adult; Aged; Child; Child, Preschool; Concanavalin A; Female; Glomerulonephritis; Glomerulosclerosis, Focal Segmental; Humans; Lymphocyte Activation; Male; Middle Aged; Nephrosis, Lipoid; T-Lymphocytes, Regulatory

Serum from patients with idiopathic minimal-change nephrotic syndrome (INS) inhibited concanavalin A (Con A) - induced lymphocyte proliferative response and rosette formation of lymphocytes with sheep erythrocytes (E). The inhibitory effect on Con A response was observed in not only INS serum but also in hyperlipidemic serum from some glomerulonephritis and hyperlipoproteinemia and was related to the serum lipid level. However, the inhibitory effect on E rosette formation was more specific for INS and was not related to the serum lipid level. Low density lipoprotein (LDL) from INS serum was more effective than that from normal serum in the inhibition of Con A response. On E rosette formation, only LDL from INS serum had inhibitory activity. Lipoprotein depleted serum did not inhibit either Con A response or E rosette formation. From these results, we speculated that LDL of INS serum contains some specific immunosuppressive factors different from those in normal LDL.

Topics: Adolescent; Child; Child, Preschool; Concanavalin A; Glomerulonephritis; Humans; Immune Tolerance; Lipoproteins; Lipoproteins, LDL; Lymphocyte Activation; Nephrotic Syndrome; Rosette Formation

Con A stimulated lymphocytes from some patients with primary glomerular disease release in vitro a lymphokine, the vascular permeability factor (VPF). House dust sensitization was early reported among these patients. We therefore studied the action of this specific mitogen on VPF production in 58 patients with primary glomerular disease, whose 23 chosen because cutaneous house dust sensitivity. For the whole patients, house dust and Con A induced VPF production were statistically equivalent and both higher than that of unstimulated lymphocytes. Lymphocytes from the 23 house dust sensitised patients, stimulated by the allergen, produced more VPF than lymphocytes from unsensitised patients.

Topics: Capillary Permeability; Cells, Cultured; Concanavalin A; Dust; Glomerulonephritis; Humans; Lymphocytes; Lymphokines; Mitogens; Thymidine; Vascular Endothelial Growth Factor A; Vascular Endothelial Growth Factors

Palmerston North (PN) mice, a newly recognized model of systemic lupus erythematosus, were compared with autoimmune hybrid NZB/NZW mice in a study designed to examine spleen cell responsiveness to T-cell and B-cell mitogens. Modest reductions of responses to phytohemagglutinin (PHA) and concanavalin A (Con A) were noted in PN females after 24 weeks of age; these responses were reduced significantly in NZB/NZW females. In contrast, male PN and NZB/NZW mice responded actively to PHA and Con A throughout the first year of life. Responses to lipopolysaccharide were not affected by age or sex. Anti-DNA antibody levels, blood urea nitrogen, and glomerular histology were analyzed to determine if autoantibody production or renal failure correlated with suppressed mitogenic responsiveness. These factors, examined singly and together, were not as important as age. In this system, age and sex did not influence spleen cell responses to mitogens in normal CD-1 mice. Age and sex were of minimal importance in determining responses to T-cell mitogens in the recently defined PN model of autoimmunity. In contrast, age and sex exerted strong influences upon responses to PHA and Con A in the NZB/NZW model of lupus.

Topics: Age Factors; Animals; Autoantibodies; B-Lymphocytes; Concanavalin A; DNA; Female; Glomerulonephritis; Lipopolysaccharides; Lupus Erythematosus, Systemic; Lymphocyte Activation; Male; Mice; Phytohemagglutinins; Sex Factors; Spleen; T-Lymphocytes

This work was undertaken to determine the cellular abnormalities that could explain the high levels of serum IgA frequently found in patients with IgA nephropathy. Seventeen control subjects and twenty-seven patients who had received no therapy were studied. After in vitro pokeweed mitogen (PWM) stimulation, significantly higher amounts of IgA were produced by peripheral blood mononuclear cells (PBM) of patients when compared with those of the control group (560 +/- 97 vs 231 +/- 57 ng/ml, P less than 0.0025). No differences were observed in the synthesis of IgG and IgM. Twenty out of twenty-seven patients presented an increase in the percentages of OKT4+ cells (mean + 2 SD), in relation to the control group, with normal or elevated percentages of OKT8+ cells. The OKT4+/OKT8+ cell ratio was elevated in 12 out of 27 patients. All patients presented some abnormality in the generation of IgA-specific suppressor cells at variable doses of concanavalin A (Con A) on in vitro PWM-stimulated culture of PBM. In both assays low doses of Con A (2.5 micrograms/ml) induced a certain suppression of IgA synthesis in patients that was not observed in the majority of the control group. At these doses some patients also showed an enhancement in the synthesis of IgG and IgM. On the contrary, higher doses of Con A (50 micrograms/ml) produced significantly less IgA suppression than the controls. Normal IgA-suppression values were found at 10 micrograms/ml of Con A. T cells obtained from patients were significantly more efficient than T cells from controls in providing IgA-helper activity for normal allogeneic enriched B cells (P less than 0.025) in PWM-stimulated cocultures. These results show that patients with IgA nephropathy present, after mitogen stimulation in vitro, a specifically increased production of IgA as well as an augmentation in the activity of IgA-helper T cell and a deregulation on IgA-suppressor T-cell function. According to these data, it is suggested that the alteration observed in helper T cells might precede that of suppressor T cells. These immunoregulatory abnormalities might contribute to the pathogenesis of the disease.

Topics: Adolescent; Adult; Antibodies, Monoclonal; Cells, Cultured; Concanavalin A; Dose-Response Relationship, Drug; Female; Glomerulonephritis; Humans; Immunoglobulin A; Male; Middle Aged; Pokeweed Mitogens; T-Lymphocytes; T-Lymphocytes, Helper-Inducer; T-Lymphocytes, Regulatory

Regulation of the immune response was studied in 22 patients with IgA nephropathy. A significant increase in the IgA production by Pokeweed-stimulated peripheral mononuclear cells maintained in culture for seven days was observed. These patients had significantly less IgA suppressor cell activity, as assessed by the Concanavalin A-generated suppressor cell assay, than the normal controls. The fact that most of the patients studied had increased activity of helper T cells on IgA synthesis, together with an augmentation in the percentage of OKT4+ cells, suggest that the abnormalities in helper T cell function might be the primary defect in this nephropathy. The existence of similar alterations in some of the healthy relatives of the patients further supports a genetic basis for susceptibility to this disease.

Topics: Concanavalin A; Female; Glomerulonephritis; Humans; Immunoglobulin A; Male; Pokeweed Mitogens; Stimulation, Chemical; T-Lymphocytes; T-Lymphocytes, Helper-Inducer; T-Lymphocytes, Regulatory

Twelve patients with type I membranoproliferative glomerulonephritis (MPGN) have been studied. All had normal renal function, none a nephrotic syndrome, and none was on therapy. In 7/12 serum C3 and/or C4 were low. T cell subsets were analysed with OKT monoclonal antibodies and Ts function (TsF) was studied by the Concanavalin-A Enhancement test (Con-A E) and with a new assay where native OKT8+ cell function only is explored (OKT8-DEP PWM test). OKT4/OKT8 ratio was lower than controls (p less than 0.025). TsF, as studied by the Con-A E was unchanged, while OKT8-DEP PWM test showed a marked decrease (p less than 0.005). Hypocomplementaemic patients (H), as compared with normo-complementaemic patients (N), had lower OKT4/OKT8 ratio (p less than 0.01) while TsF was unchanged in both groups. These results are consistent with a functional defect of Ts activity in type I MPGN. Increased OKT8+ cells may be a compensatory response, and hypocomplementaemia may be a marker of this defect.

Topics: Adult; Antibodies, Monoclonal; Complement C3; Complement C4; Concanavalin A; Female; Glomerulonephritis; Humans; Male; Middle Aged; Pokeweed Mitogens; Stimulation, Chemical; T-Lymphocytes; T-Lymphocytes, Regulatory

Lymphocyte suppressive activity after stimulation with Con A and lymphocyte function as the effectors in the ADCC test had been examined in 68 patients with chronic glomerulonephritis (GN) and in 20 healthy controls. Lymphocyte suppressive activity was lower in patients with chronic GN than in the healthy individuals. In regard to chronic proliferative GN and mesangial GN the difference was statistically significant. The lymphocyte efficiency in the ADCC test was generally adequate in patients with chronic GN and none of the morphological types showed significant deviation from the control group. In the general analysis of patients with chronic proliferative, mesangial, membrano-proliferative and membranous GN a decrease of lymphocyte suppressive activity below the lower standard limit has been detected (45% of cases). A similar defect in lymphocyte function in the ADCC test has been found in 18.6%. A statistically significant relationship between the lymphocyte function disorders and the high clinical dynamism of GN has been noticed, although in some cases there was a deviation from this tendency. It is supposed that circulating immune complexes, detected in some patients with chronic GN are not the only decisive factors responsible for defects in lymphocyte function.

Topics: Adult; Antibody-Dependent Cell Cytotoxicity; Chronic Disease; Concanavalin A; Female; Glomerulonephritis; Humans; Lymphocytes; Male; Middle Aged; T-Lymphocytes, Regulatory

Topics: Adult; Aged; Concanavalin A; Glomerulonephritis; Humans; Immunity, Cellular; Kidney Diseases; Lymphocyte Culture Test, Mixed; Middle Aged; Nephrosis, Lipoid; T-Lymphocytes, Regulatory

Cell-mediated immunity (CMI) was evaluated in 8 patients with focal glomerular sclerosis (FGS), 50 patients suffering from chronic mesangial proliferative glomerulonephritis without renal insufficiency and 24 healthy controls. The following parameters were measured: delayed skin reactivity to purified protein derivative, circulating lymphocytes, lymphocyte cell-surface markers (neuraminidase-treated sheep erythrocyte and erythrocyte-antibody-complement rosettes) and functional markers (mitogenic responses to concanavalin A and phytohemagglutinin). The FGS patients with nephrotic syndrome (NS) had a significant depression in CMI, characterized by decreased responses of the lymphocytes to both concanavalin A and phytohemagglutinin, impaired delayed hypersensitivity to purified protein derivative and a decreased proportion of T lymphocytes as compared with normal subjects. In contrast, the levels of all CMI parameters studied in FGS patients in remission and in patients with chronic glomerulonephritis with or without NS did not differ from normal subjects. Thus, the majority of FGS patients with NS demonstrated an impaired response in a CMI assay system. The possible significance of these phenomena in the pathophysiology of FGS is discussed.

Topics: Adolescent; Adult; B-Lymphocytes; Concanavalin A; Female; Glomerulonephritis; Glomerulosclerosis, Focal Segmental; Humans; Hypersensitivity, Delayed; Intradermal Tests; Leukocyte Count; Lymphocyte Activation; Lymphopenia; Male; Middle Aged; Phytohemagglutinins; T-Lymphocytes

Topics: Adult; Concanavalin A; Female; Glomerulonephritis; Humans; Immunoglobulin A; Immunologic Techniques; Male; T-Lymphocytes, Regulatory

Suppressor cell activity (SCA) was analyzed in 8 patients with idiopathic membranous nephropathy (MN) and in 11 patients with chronic proliferative glomerulonephritis (CGN). We have assessed the ability of peripheral blood lymphocytes (PBL) stimulated by concanavalin A (Con A) to inhibit the proliferative response on normal allogenic lymphocytes by both Con A and phytohemagglutinin (PHA). It was found that the MN patients with nephrotic syndrome (NS) had significantly increased levels of suppression index (SI) when compared to the values obtained with normal controls. In contrast, the mean suppression values in the PBL from MN patients in remission and CGN patients with or without NS, whether the mitogen used was Con A or PHA, were similar to those of the control subjects. Thus, the majority of MN patients wih NS demonstrated an alteration in Con-A-induced SCA. The possible significance of these phenomena in the pathophysiology of MN is discussed.

Topics: Adult; Chronic Disease; Concanavalin A; Dose-Response Relationship, Immunologic; Female; Glomerulonephritis; Humans; Immunoglobulin A; Lupus Erythematosus, Systemic; Lymphocyte Activation; Male; Middle Aged; T-Lymphocytes, Regulatory

Suppressor cell activity (SCA) was analyzed in 8 patients with focal glomerular sclerosis (FGS) and 11 patients with chronic proliferative glomerulonephritis (CGN). We have assessed the ability of peripheral blood lymphocytes (PBL) stimulated by concanavalin A (Con A) to inhibit the proliferative response of normal allogeneic lymphocytes by both Con A and phytohemagglutinin (PHA). It was found that the FGS patients with nephrotic syndrome (NS) had significantly increased levels of suppression index when compared to the values obtained with normal controls. In contrast, the mean suppression values in the PBL from FGS patients in remission and CGN patients with or without NS, whether the mitogen used was Con A or PHA, were similar to those of the control subjects. Thus, the majority of FGS patients with NS demonstrated an alteration in Con A-induced SCA. The possible significance of these phenomena in the pathophysiology of FGS is discussed.

Topics: Adolescent; Adult; Chronic Disease; Concanavalin A; Female; Glomerulonephritis; Glomerulosclerosis, Focal Segmental; Humans; Male; Middle Aged; Nephrotic Syndrome; Phytohemagglutinins; T-Lymphocytes, Regulatory

Topics: Adolescent; Adult; Chronic Disease; Concanavalin A; Female; Glomerulonephritis; Humans; Lupus Erythematosus, Systemic; Male; Middle Aged; Phytohemagglutinins; T-Lymphocytes, Regulatory

Topics: Adolescent; Adult; Child; Concanavalin A; Female; Glomerulonephritis; Hematuria; Humans; Immunoglobulin A; Immunoglobulin G; Immunoglobulin M; Immunoglobulins; Lymphocyte Activation; Lymphocytes; Male; Pokeweed Mitogens; Receptors, Antigen, B-Cell

Topics: Animals; Concanavalin A; Female; Fluorescent Antibody Technique; Glomerulonephritis; Immunity, Cellular; Kidney; Kidney Diseases; Lymph Nodes; Lymphocyte Activation; Male; Mice; Mice, Inbred Strains; Phytohemagglutinins; Prostaglandins E; Proteinuria; Spleen; T-Lymphocytes; Thymus Gland

Topics: Aging; Anemia, Hemolytic; Animals; Antibodies, Antinuclear; Autoantibodies; Colony-Forming Units Assay; Concanavalin A; Coombs Test; DNA; Female; Glomerulonephritis; Hemolytic Plaque Technique; Lipopolysaccharides; Male; Mice; Mice, Inbred NZB; Mice, Nude; Mutation; Phytohemagglutinins; Proteinuria; Rabbits; Receptors, Antigen, B-Cell; Sheep

Tests on blastic transformation of peripheral blood lymphocytes after stimulation with nonspecific mitogens (PHA, Con A, PWM) were performed on 55 patients suffering from glomerulonephritis and 32 persons belonging to the control group. On the basis of results obtained, the patients with glomerulonephritis were divided into three groups. The first, comprised patients with acute proliferative glomerulonephritis in whom the values of blastic transformation after stimulation by three mitogens used did not differ from the control group. The second, comprised patients with chronic proliferative, membraneous-proliferative, and membraneous glomerulonephritis. In 1/3 of them, a decrease blastic response to one of three mitogens was observed which was most often connected with stimulation by Con A. The third group comprised patients in the active phase of submicroscopic glomerulonephritis and lupus nephritis showing the lowest values of blastic transformation. The estimation of mitogen-induced blastic transformation was repeated in 17 patients after several weeks of nonsteroid anti-inflammatory drug therapy. After the treatment, values of spontaneous blastic transformation decreased statistically significantly. The mean values of mitogen-stimulated blastic transformation were also lower after the treatment, but the difference was not statistically significant.

Topics: Acute Disease; Adolescent; Adult; Chronic Disease; Concanavalin A; Female; Glomerulonephritis; Humans; Lymphocyte Activation; Male; Middle Aged; Mitogens; Phytohemagglutinins; Pokeweed Mitogens

The activity of IgA-specific suppressor T cells was lower in eight patients with IgA nephropathy than in six patients with chronic proliferative glomerulonephritis without glomerular deposition of IgA, two patients with acute glomerulonephritis, or five healthy adult controls. It was determined by the quantitation of immunoglobulins produced from pokeweed mitogen-stimulated B cells cultured with the T cell supernatant (TCS) obtained from concanavalin A-stimulated T cells. Results from a study on an identical twin sister with IgA nephropathy suggested that the decreased activity of IgA-specific suppressor T cells might not be a cause but a result of increased IgA-bearing lymphocytes and serum IgA in patients with IgA nephropathy.

Topics: B-Lymphocytes; Concanavalin A; Female; Glomerulonephritis; Humans; Immunoglobulin A; Immunoglobulins; Kidney Diseases; Pokeweed Mitogens; T-Lymphocytes

An experimental model of glomerulonephritis was produced by the in situ formation of immune complexes directly in the glomerular capillary wall. Perfusing the lectin concanavalin A (Con A) into the left renal arteries of rats led to its binding diffusely to the glycoproteins of the glomerular capillary wall of only that kidney in each animal. The subsequent reaction with anti-Con A antibody (either administered systemically or actively induced) resulted in an exudative and proliferative glomerulonephritis confined to the Con A perfused kidney. Immunofluorescence disclosed the diffuse deposition of immunoglobulin, Con A, and C3 in the perfused, but not the unperfused kidney. The quantitative relationship between antigen and antibody binding and histologic outcome was determined. Since lectins have been found in mammalian tissues, as well as in infectious agents that are pathogenic in man, a series of events conceptually similar to this in situ model may occur in some cases of glomerulonephritis in man.

Topics: Animals; Antibody Formation; Antigen-Antibody Complex; Binding Sites, Antibody; Capillaries; Concanavalin A; Disease Models, Animal; Fluorescent Antibody Technique; Glomerulonephritis; Glycoproteins; Kidney Glomerulus; Male; Rats

Peroxidase labeled concanavalin A (Con A) permits the detection of some saccharide determinants. This histochemical technique permits the visualization of cellular pathological modifications not observed with other methods. Its use in an ultrastructural study of nephritis induced by a single injection of aminonucleoside demonstrated the following in podocytes. The Con A positive endoplasmic reticulum (ER), essentially the rough ER, lost its normal linear and network appearance to take on a dot dash pattern. ER contents but not attached ribosomes and membranes were Con A positive. The dot dash pattern, due to a fragmentation of the ER, appeared prior to the onset of proteinuria and was attenuated before the disappearance of proteinuria. These changes of the ER were not observed in other proteinuric states. This suggests that aminonucleoside can damage the synthesis apparatus of podocytes, revealed by the Con A method.

Topics: Animals; Concanavalin A; Cytoplasm; Endoplasmic Reticulum; Glomerulonephritis; Histocytochemistry; Kidney Glomerulus; Proteinuria; Puromycin Aminonucleoside; Rats; Vacuoles

Cell-mediated immunity of lymphocytes to group A, type T 12, streptococcal cell wall extract was evaluated by measurement of DNA synthesis in cultures of lymphocytes from healthy controls and from glomerulonephritic patients. Cells from adult healthy persons regularly responded to this antigen, whereas cord blood lymphocytes did not. Several additional experiments suggested that the response in normal controls was due to a specific immune response and was not caused by a nonspecific mitogenic effect of the cell wall antigens. In a group of 17 patients with progressive glomerulonephritis (PGN) and 10 with nonprogressive glomerulonephritis (IRGN) the level of response was comparable to that of healthy controls. In the PGN group the response was significantly lower after 4 days, but this difference disappeared after 6 days. Thus, this method failed to differentiate between health and disease. The presence of anti-streptococcal cell wall antigen antibodies was tested using a passive hemagglutination technique. Only 1 of 6 controls had a demonstrable antibody titer, whereas 15 of 26 nephritic patients had detectable antibodies and 10 of them had titers greater than 1/64. Our findings suggest the possibility of a relationship between streptococcal bacteria and progressive glomerulonephritis.

Topics: Antibodies, Bacterial; Antibody Formation; Antigens, Bacterial; Cell Wall; Cells, Cultured; Concanavalin A; DNA; Glomerulonephritis; Hemagglutination; Humans; Immunity, Cellular; Lectins; Lymphocytes; Streptococcal Infections; Streptococcus; Time Factors