Isologous monoclonal antibodies can induce anti-GBM glomerulonephritis in rats.

Injection of isologous monoclonal antibodies (SR2, SR3) caused anti-glomerular basement membrane antibody-induced glomerulonephritis (anti-GBM nephritis) in WKY/NCrj rats. The antibodies were obtained from hybridoma cells derived from fusion of the spleen of a nephritic WKY/NCrj rat injected with rat solubilized renal basement membranes with adjuvant, and mouse SP2-myeloma cells. They belonged to the rat IgG2a subclass and bound to rat kidney in a linear pattern along the glomerular and tubular basement membranes. Histological changes in glomeruli were detected at day 1 after the injection; proteinuria with haematuria appeared on day 2; and proteinuria became severe and reached a plateau by day 5. These results demonstrate that anti-GBM nephritis can even be induced by an isologous monoclonal antibody and that the rat IgG2a subclass is at least nephritogenic. The experimental model of anti-GBM nephritis with isologous monoclonal antibodies makes it possible and easier to analyse further the mechanism of anti-GBM nephritis.