Immunological function in glomerulonephritis.

Aspects of humoral and cellular immunity and of the complement system were examined in 44 patients with glomerulonephritis, and in control subjects. A number of patients with glomerulonephritis were shown to have evidence of altered immunity which may reflect underlying mechanisms of glomerular injury. Mesangial IgA glomerulonephritis was associated with elevation of serum IgA levels (P less than 0 . 001), and focal sclerosing glomerulonephritis with raised serum IgM (P less than 0 . 001). Serum IgG levels were abnormal in 15 patients with glomerulonephritis. The haemagglutinating antibody response to tetanus toxoid was reduced in patients compared with controls. Levels of serum complement components were increased, with some exceptions, and C-reactive protein levels were also significantly raised (P less than 0.001), findings consistent with an ongoing inflammatory process. No impairment in response to recall antigens or sensitisation to dinitrochlorobenzene was found, but phytohaemagglutinin induced lymphocyte transformation was reduced in some forms of the disease.