Macrochimerism of donor type CD56+ CD3+ T cells in donor specific transfusion via portal vein following living related donor liver transplantation.

摘要

Antigens given orally or through the portal vein are known to be less immunogenic and to induce immunologic unresponsiveness. The mechanisms responsible for graft enhancement are still unclear. Moreover, in actuality, it is difficult to perform transfer of donor antigens via the portal vein in clinical transplantation. We investigated the effect of transfer of donor blood via the portal vein intra- and post-operatively in living related donor liver transplantation for recurrent multiple hepatocellular carcinoma. A 62-year-old female, who suffered from recurrent multiple hepatocellular carcinoma with hepatitis C virus, underwent living related donor liver transplantation with the right lobe of her daughter. Eleven hepatocellular carcinomas were recognized in the resected specimen. Donor blood was administered via the portal vein using a catheter inserted in the middle colic vein intra- and postoperatively. Mononuclear cells were obtained by operative liver biopsy or postoperative biopsy using fine needle aspiration biopsy, and from peripheral blood. They were analyzed by two or three color-flow cytometry using several antibodies. The differentiation between donor and recipient was estimated by means of anti-HLA antibodies of donor and recipient. The postoperative course was uneventful. She did not suffer from acute cellular rejection and was discharged on day 30 the after operation. CD56+ CD3+ T cells in the liver increased notably from 20% to 50% after transplantation. One half of the CD56+ CD3+ T cells in the liver graft were of the donor type (donor anti-HLA A2 antibody) on day 8 after surgery. Donor type CD56+ CD3+ T cells occupied 17.4% of the total CD56+ CD3+ T cells even on day 42 after the operation. Stimulation index by mixed lymphocyte reaction continued at a low level (< 2) from day 1 after the operation. Steroids were discontinued after 40 postoperative days. FK506 was also reduced to 0.5 mg/day 4 months after the operation. There was no recurrence of hepatocellular carcinoma and hepatitis C virus for two years after the operation. Macrochimerism of donor type CD56+ CD3+ T cells in a graft might be induced by the transfer of donor blood via the portal vein and may play an important role in transplantation tolerance. Inoculation of donor blood via the portal vein may also be very useful for rapid reduction of immunosuppression.