Different Antibody Response in Experimental and Spontaneous Glomerulonephritis

Abstract

The immune nephritis antibody response against the collagen and glycoprotein portions of the glomerular basement membrane (GBM) has been monitored by using either type IV collagen prepared from pepsin digests or a collagenase digest of GBM. Sheep immunized with GBM, according to Steblay, respond by developing antibodies directed against the collagen and the glycoprotein portions, respectively. Circulating antibodies directed against sheep GBM structures were not demonstrated until overt clinical disease with high serum creatinine values and proteinuria. Such antibodies could, however, be eluted from the kidneys, where they adsorbed in a linear fashion as demonstrated by immunofluorescence microscopy. In spontaneous human nephritis in Goodpasture’s syndrome, circulating antibodies were present at the time of diagnosis. These antibodies reacted only with the glycoprotein portion of the basement membrane, and not with the type IV collagen.