Role of the Spleen in Immunologic Enhancement of Kidney Grafts in Rats

Abstract

Immunologic enhancement induced with alloimmune serum specifically suppresses renal allograft rejection in the rat (1, 2, 3). Several observations suggest that the recipient has an active role in enhancement. Alloantibody, rapidly fixed to tissues, disappears from the serum four hours after administration (4), and must be given at the time of grafting to insure graft survival (5). Multiple daily injections of suboptimal amounts are ineffective (5). Furthermore, enhancement of organ grafts, instead of preventing the immune response, modifies it so that the balance between graft rejection and prolonged survival is different from a primary graft response. Thus, hemagglutinating and cytotoxic antibodies appear after grafting with the same titer and kinetics as untreated grafts (3). Cell mediated immunity is similarly present (6).