PROLONGATION OF RAT SMALL-BOWEL OR RENAL-ALLOGRAFT SURVIVAL BY PRETRANSPLANT TRANSFUSION AND OR BY VARYING THE ROUTE OF ALLOGRAFT VENOUS DRAINAGE/

Lewis rats show prolongation of survival of LBNF(1) renal allografts w hen those grafts are drained by the portal vein, or if recipients are treated with LBNF(1) bone marrow cells infused via the portal venous r oute peritransplantation. The longest survival was seen in animals in which both portal venous transfusion and graft drainage by the portal route were performed. When the same manipulations were performed for L ewis rats receiving heterotopic small bowel transplants, only in the ' 'combined treatment'' group was there significantly enhanced graft or animal survival relative to control rats. In separate studies, we exam ined the mixed leukocyte proliferation response in vitro, and IL-2 pro duction, from rats treated as above and receiving renal or small bowel transplants. In both organ transplant models, there was a good correl ation between enhanced graft survival in vivo and decreased in vitro r esponses to specific allostimulation.