A mechanism of enhancement of immune complex deposition following in situ immune complex formation in the mouse glomerulus.

The intravenous injection into mice of small amounts of heat-aggregated bovine serum albumin (BSA) results in deposition of BSA within the glomerulus. Injection of rabbit anti-BSA antibody at a time when all circulating BSA has been cleared results in in situ formation of BSA anti-BSA immune complexes with fixation of mouse C3. Subsequent injection of passively-prepared immune complexes gives much enhanced deposition of immune material when compared with mice given immune complexes alone. This paper shows that this is an antigen-specific phenomenon and not a result of non-specific trapping by damaged glomeruli. The implications of these observations on the pathogenesis of immune complex glomerulonephritis are discussed.