[C3 production by peripheral blood monocytes in patients with membranoproliferative glomerulonephritis and...

Peripheral blood monocytes (PBM) and T cells from patients with membranoproliferative glomerulonephritis (MPGN) and poststreptococcal glomerulonephritis (PSAGN) were measured for the production on C3 and interferon-gamma respectively using an enzyme-linked immunosorbent assay. Testing of MPGN and PSAGN patients at acute stage showed that C3 levels by PBM were significantly higher than those of normal controls, whereas the levels of PSAGN patients at convalescent stage dropped within the range of normal controls. Levels of C3 production by PBM inversely correlated with serum C3 in both MPGN and PSAGN patients. Interferon-gamma production by T cells of MPGN patients were significantly higher than those of normal controls, while in PSAGN patients the levels, although not significantly elevated at acute stage, increased significantly at convalescent stage. These results suggest that hyperproduction of C3 by PBM in both hypoC3 disorders is likely due to activation of the cells by not yet determined antigens or immune complexes, but the effects of T cells on the activated PBM in MPGN differ from in PSAGN patients probably due to distinct antigens or immune complexes.