Antibody-mediated injury to proximal tubules in the rat kidney induced by passive transfer of homologous anti-brush border serum

Abstract

Study of the natural history of Heymann nephritis in rats has led to the suggestion that antibodies to brush border are responsible for injury to proximal tubules. To obtain direct evidence that antibodies to brush border are cytotoxic to cells of the proximal tubular epithelium, passive transfer experiments were performed. Rats with serum sickness glomerulonephritis were recipients of homologous anti-brush border serum. Forty-eight hours after the first injection of anti-brush border serum, immunoglobulin was bound to the luminal border of proximal tubules. Fixation of immunoglobulin was associated with loss of microvilli and proliferation of cells of the tubular epithelium. The changes in proximal tubules observed in passive transfer experiments were similar to those seen in rats with Heymann nephritis and were not observed in animals which received injections of normal rat serum. It appears that damage of renal tubules may be the consequence of deposition of antibodies along the plasma membrane of tubular cells.