Prolonged survival of rat hepatic allografts after pretransplant intraportal administration of recipient blood to the donor

Background: We investigated the effect of the pretransplant administration of recipient''s blood to donor on rat hepatic allograft survival. Methods: Serum levels of interferon (IFN)-γ were determined after transplantation. Immunocompetent cells from the donor were identified with anti-donor class II MHC (RT1Ba) (OX-76) antibodies. The number of donor-derived CD4+ and CD8+ T cells in hepatic allografts or recipient spleen was determined. Results: LEW rats transplanted with hepatic allografts from ACI rats survived a mean of 11.1±2.1 days. Pretreatment intravenous administration of recipient LEW blood did not prolong the survival of hepatic allografts (10.5±1.7 days). In contrast, pretreatment intraportal administration of recipient LEW blood significantly increased the survival of LEW recipients with ACI livers to 31.7±7.6 days (Table 1). The ratio of ox76+CD4+ or ox76+CD8+ T cell to CD4+ or CD8+ cell was significantly greater (25.6% versus 5.7%, 26.6% versus 6.8%) in hepatic allografts pretreated with pretransplant intraportal administration of LEW recipient blood, rather than those cells in recipient spleen (46.2% versus 34.4%, 63.7% versus 71.4%). Conclusions: Pretransplant intraportal administration of recipient LEW blood to ACI donor rats prolonged the survival of hepatic allografts. This may be associated with the regional graft-versus-host reaction. [Copyright &y& Elsevier]