Recipient blood pre-transplant transfusion prolongs hepatic allograft survival in rats

Background The pre-transplant administration of donor antigens to recipients is reported to prolong transplanted organ survival. We investigated the effect of pre-transplant intraportal administration of recipient blood on rat hepatic allograft survival. Materials and methods Male LEW (RT1l) and ACI (RT1a) rats were used as transplant recipients and donors, respectively. Before transplantation, donors were transfused with recipient blood. Experimental animals were divided into groups as follows: group I, no treatment; group II, pre-treatment with recipient blood via the penile vein 7 days before transplantation; group III, pre-treatment with recipient blood via the portal vein 5 days before transplantation; and group IV, pre-treatment with recipient blood via the portal vein 7 days before transplantation. Serum interferon (IFN)-γ concentrations were measured post-operatively. Results Animals in group I survived a mean of 10.1 ± 0.7 days. The survival of groups II and III was 10.6 ± 1.6 and 13.1 ± 0.9 days, respectively. The survival rate in group IV was prolonged significantly to 33.7 ± 2.6 days. Serum concentrations of IFN-γ were increased significantly in group IV, as compared with group I. The ratio of OX76+CD4+ or OX76+CD8+ T cells to OX76-CD4+ or OX76-CD8+ T cells was greater in group IV, as compared group I. OX76+CD8+ T cells from hepatic allografts in group IV expressed IFN-γ and interleukin (IL)-10, but not IL-2 mRNA. Apoptotic hepatic infiltrates were greater in group IV, as compared to group I. Conclusion The cytokine profile of donor CD8+ T cells from allografts treated by the intraportal administration of recipient blood is associated with apoptosis of graft-infiltrating cells and the prolonged survival of hepatic allografts in rats.