Anti-GBM nephritis in the mouse: severe proteinuria in the heterologous phase.

Highly reproducible anti glomerular basement membrane (GBM) nephritis has been induced in the mouse after a single injection of rabbit or goat antibody against purified homologous GBM. The severity of albuminuria was closely related to the amount of antibody given. With doses of 4 mg or more, low serum albumin concentrations, sometimes accompanied by ascites and oedema, were observed after 1 week. Glomerular injury was characterized by an initial accumulation of polymorphonuclear granulocytes followed by thrombosis and necrosis, the extent of which defined the outcome of the glomerulonephritis. With high doses of antibody the exudative lesions entered a chronic phase, while at doses lower than 2 mg remission of the lesions occurred. Immunofluorescence studies showed prompt linear fixation of the injected antibodies to the glomerular capillary wall, accompanied by immediate binding of C3 in a fine granular pattern. Fibrin deposits appeared at 2 h in some glomeruli, increased thereafter, and were present after one day in more than 90% of the glomeruli in mice that had received 4 mg of antibody. This new reproducible model in the mouse is suited for the study of the relationship between activation of mediator systems, histological lesions, and proteinuria.