concanavalin-a and Proteinuria

Lymphocyte ectoenzymes with immunomodulatory function were investigated in 11 children with minimal change disease (MCD), 9 with primary focal segmental glomerulosclerosis (FSGS), and 17 age- and sex-matched healthy children. Basal, concanavalin A (Con A)-, and pokeweed mitogen (PWM)-stimulated lymphocyte ecto-5'-nucleotidase (5'-Nu), dipeptidyl peptidase IV (DPP IV), and alkaline phosphodiesterase I (APD) activities were determined. In MCD relapse ecto-APD activity of unstimulated lymphocytes was higher than controls. Ecto-APD of Con A-stimulated lymphocytes was below controls (23.0, range 7.2-48.7 nmol/min per 10(6) lymphocytes) in all active MCD (18.7, range 7.6-32.6), during corticosteroid treatment (14.6, range 4.5-54), and in remission (13.1, range 6.1-19.6), but was significant only in remission. Con A-stimulated DPP IV was significantly lower from controls (53.8, range 19.3-85.7 nmol/min per 10(6) lymphocytes) in all active MCD (38.1, range 10.8-82.1), during treatment (37.5, range 20.2-58.7), and in remission (39.4, range 24.3-69.6). In FSGS, unstimulated lymphocyte ecto-APD activity was greater than controls. However, Con A-stimulated lymphocyte ecto-APD and DPP IV activities were not significantly different from controls. Con A stimulation of lymphocyte ecto-APD and DPP IV activity was significantly reduced in MCD relapse and in remission, but not in FSGS. Basal, Con A-, and PWM-stimulated ecto-5'-Nu in MCD and FSGS were not different from controls. These results suggest a role for abnormal T cell function in MCD but not in FSGS. The difference in mitogen-stimulated expression of these ectoenzymes suggests a different pathogenesis of childhood MCD and primary FSGS.

Topics: 5'-Nucleotidase; Adolescent; Cells, Cultured; Child; Child, Preschool; Concanavalin A; Dipeptidyl Peptidase 4; Enzyme Activation; Female; Glomerular Filtration Rate; Glomerulosclerosis, Focal Segmental; Humans; Lymphocytes; Male; Nephrosis, Lipoid; Phosphodiesterase I; Phosphoric Diester Hydrolases; Pokeweed Mitogens; Proteinuria

Despite the importance of endothelial injury and healing for primary and secondary renal disease and the availability of genetically engineered mouse models, to date no generally applicable murine disease model with site-specific renal endothelial injury has been established. We induced specific microvascular renal injury via selective renal arterial perfusion of the lectin concanavalin A (Con A) followed by sheep anti-concanavalin A and harvested tissues after 4 h, 24 h, days 3 and 7. Compared to control kidneys, histological evaluation demonstrated endothelial cell injury with subsequent complement, and platelet activation and thrombosis by light and electron microscopy. Mouse kidneys showed histologic evidence of severe glomerular and peritubular microvascular thrombosis with acute tubular necrosis, proteinuria, increased BUN and presence of schistocytes. Initial cell death of intrinsic renal cells resulted in a decrease of the glomerular cell count by 50% after 4 h followed by a proliferative response of glomerular (day 3, P < 0.05), interstitial (day 3, P < 0.05) and tubular cells leading to increased total glomerular cell count by day 7. This study establishes the Con A anti-Con A model as specific endothelial injury model in the mouse kidney providing a novel tool for investigating endothelial injury and repair mechanisms as well as elucidating the role of platelets in genetically engineered mice.

Topics: Animals; Apoptosis; Concanavalin A; Disease Models, Animal; Endothelium, Vascular; Immunohistochemistry; In Situ Nick-End Labeling; Kidney Glomerulus; Kidney Tubular Necrosis, Acute; Male; Mice; Mice, Inbred C57BL; Microcirculation; Microscopy, Electron; Mitogens; Platelet Endothelial Cell Adhesion Molecule-1; Proteinuria; Renal Circulation; Severity of Illness Index; Thrombosis; Vascular Endothelial Growth Factor A

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

We examined the effect of a fish oil-enriched diet on the development of experimental membranous nephropathy in the rat induced by administration of cationic bovine gamma globulin (CBGG). Rats were placed on a fish oil-enriched diet and control rats received a diet containing an equivalent amount of beef tallow. After 6 weeks on either diet, rats were pre-immunized and injected with CBGG. Proteinuria was significantly reduced in the fish oil-fed group as compared to the control group (160 +/- 40 mg/24 hours, n = 15, versus 280 +/- 36 mg/24 hours, n = 17, p less than 0.02). Glomerular filtration rate was also significantly higher in the fish oil-fed rats than in controls (0.91 +/- 0.07 ml/minute, n = 11, versus 0.60 +/- 0.05 ml/minute, n = 10, p less than 0.005). Glomerular production of prostaglandin E2 and thromboxane B2 the stable product of thromboxane A2, were inhibited by 68% and 70%, respectively, by the fish oil-enriched diet (n = 8, p less than 0.01 versus control). Glomerular leukotriene B4 was also inhibited by 50% in the fish oil-treated rats (n = 6, p less than 0.01), but inhibition of leukotriene B4 by the specific inhibitor L-663,536 in control rats did not ameliorate proteinuria. There was no difference in the amount of distribution of glomerular immune deposits as demonstrated by immunofluorescence and electron microscopy between the experimental and control groups. Moreover, comparable amounts of glomerular IgG deposits were present in the two groups. The specific immune response, assessed by measuring anti-BGG antibody levels, was not different between the two dietary groups, while more than 85% suppression of the splenic T- and B-cell mitogenic response to concanavalin-A and lipopolysaccharide was noted in rats fed the fish oil-enriched diet. We conclude that a fish oil-enriched diet reduces proteinuria and preserves the glomerular filtration rate in rats with CBGG-induced membranous nephropathy. Its mechanism of action remains to be established.

Topics: Animals; Antibodies; Cattle; Concanavalin A; Dietary Fats, Unsaturated; Eicosanoids; Fish Oils; gamma-Globulins; Glomerular Filtration Rate; Glomerulonephritis, Membranous; Kidney Glomerulus; Leukotriene B4; Lipopolysaccharides; Lymphocyte Activation; Proteinuria; Rats; Rats, Inbred Strains; Spleen

A glomerular permeability factor produced by human T cell hybridomas. T cell hybridomas derived from the T cells of a patient with mammal change nephrotic syndrome (MCNS) made a glomerular permeability factor (GPF). Sufficient quantities of GPF were available for further analysis and characterization. We obtained four stable clones of human T cell hybridomas which produced a glomerular permeability factor. When this factor was injected intravenously into rats, significant proteinurias were induced, and in normal human lymphocyte culture, GPF enhanced Concanavalin-A (Con-A) induced lymphocyte blastogenesis by greater than ten fold. GPF was cytotoxic to tumor cell lines of epithelial origin, but only cytostatic to tumor cells of hematopoietic origin. Electron microscopy studies, with polyethyleneimine (PEI) staining, indicated that GPF induced the changes in the arrangement of PEI particles and partial fusion of glomerular epithelial cells in the rats given this factor intravenously. The molecular weight of GPF were estimated to be between 60,000 and 160,000 daltons. The molecular weight of the factor and its TNF like activity, we speculated that the factor was a lymphokine, like lymphotoxins.

Topics: Animals; Concanavalin A; Drug Synergism; Epithelium; Humans; Hybridomas; Lymphocyte Activation; Lymphokines; Molecular Weight; Nephrosis, Lipoid; Proteinuria; Rats; T-Lymphocytes; Tumor Cells, Cultured

Although circulating phagocytic cells are important mediators of glomerular injury, their recruitment mechanisms are not completely understood. In this study, the intraglomerular trafficking of leukocytes was characterized in a rat model of acute glomerular injury induced by nephrotoxic serum (NTS). Polymorphonuclear (PMN) cells infiltrated, then disappeared rapidly, reaching a peak at 2 hr. By 6 hr the PMN migration had almost reversed but small numbers persisted until Day 7. The monocyte influx began almost simultaneously but was of lesser magnitude. However, the number of ED-1+ monocytes increased progressively from 60 min to reach a plateau by Day 2 and persisted to the end of the study (Day 28). Quantitation of intraglomerular Ia+ cells suggested in situ activation of monocytes within the glomeruli. Increased Ia+ cells were first evident on Day 2. By Day 5, 80% of the intraglomerular macrophages were Ia+. Complement depletion with cobra venom factor abrogated early albuminuria, delayed the initial PMN influx, but failed to attenuate monocyte migration. T lymphocytes appeared briefly between 10 min and 2 hr. In vitro proliferation study failed to demonstrate lymphocyte sensitization to glomerular basement membrane (GBM) antigens. A unique population of cells (OX19 OX8+), possibly representing natural killer cells, was present from Day 1 to Day 14. During the secondary wave of proteinuria (autologous phase), all leukocytes had disappeared except for macrophages and a small number of OX19-, OX8+ cells. A complex intraglomerular migration of leukocytes was triggered by the binding of nephrotoxic antibodies to GBM antigens. We speculate that this cascade involves several cell-to-cell interactions necessary for the full expression of glomerular injury.

Topics: Animals; Basement Membrane; Cell Division; Cell Movement; Complement System Proteins; Concanavalin A; Disease Models, Animal; Fluorescent Antibody Technique; Kidney Cortex; Kidney Glomerulus; Leukocytes; Male; Monocytes; Nephritis; Neutrophils; Phagocytes; Proteinuria; Rats; Rats, Inbred Lew

Peripheral blood mononuclear cells (PBMC) from patients with minimal-change nephrotic syndrome (MCNS) were tested for their ability to produce a factor which increases the urinary protein excretion levels of rats. It was shown that enhanced proteinuria can be produced in 8-hour urine specimens from rats by the injection of concentrated supernatants of cultured concanavalin-A-stimulated PBMC of patients with MCNS, but not from other nephrotics or normal subjects. The increase in urinary protein excretion was associated with a significant alteration of glomerular epithelial cells similar to that seen in MCNS. These results suggest that in MCNS, PBMC release a factor, which we termed a glomerular permeability factor (GPF), causing changes in glomerular permeability with resulting proteinuria.

Topics: Adolescent; Adult; Animals; Concanavalin A; Female; Humans; Kidney Glomerulus; Lymphocyte Activation; Male; Middle Aged; Nephrosis, Lipoid; Permeability; Proteinuria; Rats; Rats, Inbred Strains; Urine

Idiopathic nephrotic syndrome (INS) is associated with a disorder of T-lymphocyte function, and an enhanced production of a vasoactive lymphokine, the vascular permeability factor (VPF). In an attempt to evaluate lymphocyte activation in various phases of INS, we measured beta 2-microglobulin (beta 2m) levels in lymphocyte culture supernatants (LCS). In 23 cases of untreated active INS, beta 2m levels in unstimulated LCS were significantly increased in comparison with those of 13 cases of untreated INS in complete remission (p less than 0.001), of 17 cases of active membranous nephropathy (p less than 0.01) and of 14 controls (p less than 0.001). In 13 patients treated with cyclosporine (Cs) (3-4.5 mg/kg/d) during 3 months, beta 2m levels were within the normal range. Although the beta 2m of 7 Cs patients without proteinuria was lower than 5 Cs patients with residual proteinuria, the difference was not statistically significant. In 15 prednisone(Pr)-treated INS patients, beta 2m levels were normalized. However their beta 2m levels were lower in 8 cases of complete remission than in 7 cases of persistent proteinuria (p less than 0.05). Concanavalin-A stimulation increased beta 2m amounts in all groups with a similar magnitude. In vitro addition of Cs (100 ng/ml) inhibited both beta 2m and VPF elevations observed in active INS. beta 2m level and VPF activity were significantly correlated (r = 0.54, p less than 0.01). High levels of beta 2m in LCS from INS are the consequence of an enhanced cellular synthesis and they are inhibited by Pr and Cs. Thus beta 2m increase in INS indeed reflects lymphocyte activation.

Topics: Adolescent; Adult; Aged; beta 2-Microglobulin; Cells, Cultured; Concanavalin A; Cyclosporins; Female; Humans; Lymphocyte Activation; Lymphocytes; Male; Middle Aged; Nephrotic Syndrome; Proteinuria; Time Factors

We examined the effect of methyl-B12 on the immune system. As a result, it was revealed that methyl-B12 enhanced antibody production in the in vitro system and that this activity was the strongest with methyl-B12 among the homologues of B12 examined, being nearly as strong as that of Levamisole. It was also revealed that methyl-B12 can exert an enhancing activity on the induction of suppressor T cells Con A. These facts suggest that methyl-B12 has a therapeutic effect against spontaneous incidence of diseases in NZA/W mice. These immunomodulative activities of methyl-B12 and their therapeutic significance against immune disorders were discussed.

Topics: Animals; Antibody Formation; Antibody-Producing Cells; Cell Survival; Concanavalin A; Female; Hemolytic Plaque Technique; Levamisole; Lymphocyte Activation; Mice; Mice, Inbred C57BL; Mice, Inbred NZB; Proteinuria; Sheep; Spleen; T-Lymphocytes, Regulatory; Vitamin B 12

Natural thymocytotoxic autoantibody (NTA) developed spontaneously in New Zealand Black (NZB) mice consists of two autoantibodies in terms of target cell specificity. One of the autoantibodies, NTA-2, is strongly cytotoxic only against desialized lymphocytes, whereas the other one, NTA-1, is cytotoxic against both intact thymocytes and asialolymphocytes. To study the pathogenic role of NTA in murine autoimmunity, DBA/2 mice were injected every other day with affinity-purified NTA (NTA-1, NTA-2). Control mice received normal mice sera (NMS) or saline. After 20 days of treatment, spleen cells from DBA/2 mice treated with NTA-1 or NTA-2 showed a significant increase in the number of anti-ssDNA plaque-forming cells and IgM-producing cells. Sera from NTA-treated mice showed greater DNA binding than sera from control mice did. The levels of proteinuria were moderately increased in NTA-2-treated mice. Con A responsiveness of thymocytes was markedly reduced in NTA-2-treated mice. On the other hand, Con A-activated spleen cells from both control and NTA-treated mice equally suppressed anti-SRBC antibody production in vitro, suggesting that NTA treatment didn't affect the direct precursors of suppressor T cells. Finally, prior absorption of NTA-1 by thymocytes prevented its ability to induce anti-DNA antibodies; however, prior absorption of NTA-2 by thymocytes didn't affect its activity.

Topics: Animals; Antibody Formation; Antilymphocyte Serum; Autoantibodies; Concanavalin A; Cytotoxicity, Immunologic; DNA; DNA, Single-Stranded; Female; Lymphocyte Activation; Male; Mice; Mice, Inbred DBA; Mice, Inbred NZB; Neuraminidase; Proteinuria; Spleen; T-Lymphocytes; T-Lymphocytes, Regulatory

Suppressor cell activity (SCA) was analysed in 28 patients with lipoid nephrosis (LN) 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 phytohaemagglutinin (PHA). It was found that the LN patients in the earlier phase of relapse had significantly increased levels of suppression index (SI) were compared with the values obtained with normal controls. In contrast, the mean suppression values in the PBL from LN patients in remission and CGN patients with or without nephrotic syndrome, whether the mitogen used was Con A or PHA, were similar to those of the control subjects. Moreover, when individual patients were followed through their clinical illness, LN patients had high levels of SI, particularly in the beginning of acute exacerbations; the SI levels than decreased sharply in the latter phase of relapse and again increased to relatively normal levels with the onset of clinical remission. These in vitro findings suggest that there exists an alteration in Con A-induced SCA in a group of patients with LN.

Topics: Adolescent; Adult; Child; Concanavalin A; Female; Humans; Hypoproteinemia; Kidney; Lymphocyte Activation; Male; Middle Aged; Nephrosis, Lipoid; Prednisolone; Proteinuria; T-Lymphocytes, Regulatory

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

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

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

Lethally irradiated mice protected with allogeneic fetal liver cells or with syngeneic or allogeneic marrow and spleen cells treated with antisera to mouse immunoglobulins or to the T cell-associated theta antigen and their controls were observed for up to 750 days. The best survival rates were found in the large groups given syngeneic marrow and spleen or allogeneic fetal liver cells (70-85% 700-day survival); in contrast, 43% of the group injected with allogeneic cells treated with anti-theta serum and 19% of those given antiimmunoglobulin-treated cells were alive 700 days postradiation. Pulmonary infection was the most frequent cause of death of long-term survivors in all groups. Tumor incidence was increased in recipients of allogeneic cells (13% versus 4% among syngeneic chimeras), but the renal pathology seen in these groups was no greater than that noted in the syngeneic controls. Beginning 600 days after irradiation, mice from experimental and control groups were killed and their spleens were cultured with thymus-dependent antigens and the mitogens concanavalin A and lipopolysaccharide, Escherichia coli. The most frequent finding in all groups was mild to moderate impairment of T cell-dependent responses.

Topics: Animals; Bone Marrow Cells; Bone Marrow Transplantation; Concanavalin A; Dinitrophenols; Embryo, Mammalian; Escherichia coli; Fetus; Fluorescent Antibody Technique; gamma-Globulins; Immune Sera; Lipopolysaccharides; Liver; Lymphocyte Activation; Lymphocyte Culture Test, Mixed; Lymphocyte Transfusion; Male; Mice; Mice, Inbred C57BL; Mice, Inbred CBA; Polysaccharides, Bacterial; Proteinuria; Radiation Chimera; Spleen; Transplantation, Homologous; Transplantation, Isogeneic

The administration of Concanavalin A (Con A) to young New Zealand (NZB/W) mice has been previously found to render them tolerable to BGG. The corresponding mechanism is unknown but is consistent with other observations that Con A is capable of activating a suppressor T cell population. We have further explored this possibility by giving New Zealand mice Con A from 1 month until 11 months of age and monitoring several known immunologic abnormalities. Con-A-treated mice, in contrast to littermate controls, were found to have lower anti-DNA levels, less proteinuria, a better response to primary sheep red cell immunization and normally rejected skin allografts.

Topics: Age Factors; Animals; Antibodies; Antibody Formation; Antigens; Concanavalin A; DNA; Erythrocytes; Female; Graft Rejection; Hemolytic Plaque Technique; Lymphocyte Activation; Male; Mice; Mice, Inbred C57BL; Mice, Inbred NZB; Proteinuria; Sheep; Skin Transplantation; Transplantation Immunology; Transplantation, Homologous