IMPAIRED REGULATION OF ERYTHROCYTE AUTOANTIBODY PRODUCTION AFTER SPLENECTOMY

Abstract

C3H mice were given 4 i.p. injections, each of 2 .times. 108 WAG rat RBC [red blood cells] at weekly intervals. Production of erythrocyte autoantibodies [Auto-Ab] elicited by the cross-reacting rat RBC was assessed using the average direct Coombs'' test (DCT) score. Auto-Ab production reached higher levels and persisted significantly longer in mice splenectomized 15 days before the 1st injection of rat RBC. Increased production of Auto-Ab was not prevented by injecting each splenectomized mouse i.v. with 5 .times. 107 syngeneic spleen cells immediately after splenectomy. Splenectomy of mice already DCT+ significantly prolonged Auto-Ab production which was not prevented by injections of 108 cells prepared from spleens removed at splenectomy. Spleen cell transfer from mice already DCT+ to mice before injections of rat RBC were started in the recipients caused significant reduction in amount of RBC produced. This suppression of Auto-Ab production was greater in unsplenectomized mice than in splenectomized mice. The spleen is involved in regulation of these erythrocyte Auto-Ab responses. The cellular component of the spleen and the splenic architecture and/or environment may contribute to regulation of Auto-Ab responses.