The role of T cells in the mediation of glomerular injury in Heymann's nephritis in the rat.
Heymann's nephritis (HN), a rat model of the membranous glomerulonephritis in man, is thought to be mediated by auto-Ig with subsequent activation of C. Whether T cell mechanisms are involved in the mediation of HN, apart from CD4+ cells providing help for auto-Ig production, was examined by treatment with mAb specific for T cell subsets for 6 weeks after immunization to induce HN. Anti-CD4 mAb therapy totally prevented proteinuria, in that at 6, 8, and 12 week treated rats had less than 15 mg/day of protein compared to controls that all had greater than 260 mg/day. Ig and C deposition in the glomerulus was significantly less and auto-Ig titers in serum were partially suppressed by anti-CD4 therapy. Anti-CD8 mAb therapy markedly reduced proteinuria at all time points, for example at 6 weeks there was 51 +/- 40 mg/day compared to 183 +/- 120 mg/day (P = 0.0003), but had no effect on auto-Ig titers or on Ig and C deposition in the glomerulus. A non-specific effect of high dose mouse mAb therapy was excluded by the findings that a mAb that did not bind to rat cells had no effect on the induction of HN and that serum C was not depleted in any of the mAb treated animals. A role for T effector mechanisms was further supported by the finding that therapy with mAb to T cell receptor alpha/beta chain or with cyclosporine also markedly delayed the onset of proteinuria. Examination of renal biopsies showed a T cell infiltrate in glomeruli and the interstitium of the untreated HN controls that was not present in MRC Ox35 or MRC Ox8 treated groups. This infiltrate included CD4+ and CD8+ T cells and macrophages. These results suggest induction of proteinuria in HN was totally dependent upon CD4+ T cells, and that CD4+ and CD8+ cells may have a direct role in the mediation of glomerular dysfunction in HN.
Quiza
C G
CG
Department of Medicine, Stanford University School of Medicine, CA 94305-5114.
Leenaerts
P L
PL
Hall
B M
BM
D000818:Animals; D000911:Antibodies, Monoclonal / Q000008:administration & dosage; D015704:CD4 Antigens; D016827:CD8 Antigens; D016572:Cyclosporine / Q000494:pharmacology; D005921:Glomerulonephritis / Q000209:etiology* / Q000473:pathology / Q000517:prevention & control; D007678:Kidney Glomerulus / Q000276:immunology / Q000293:injuries*; D051379:Mice; D051381:Rats; D011917:Rats, Inbred Lew; D016176:T-Lymphocyte Subsets / Q000276:immunology*
D000911:Antibodies, Monoclonal; D015704:CD4 Antigens; D016827:CD8 Antigens; D016572:Cyclosporine