Total orthotopic allogeneic small bowel transplantation in rats. Attempts to ameliorate the graft-versus-host disease by irradiation and transfusions of the donor.

The effect of pretransplant specific blood transfusions and irradiation of the donor were studied in total orthotopic small bowel transplantation in rats, with the aim of ameliorating the graft-versus-host reaction. Syngeneic transplantation with or without irradiation of the donor with 10 Gy showed that small bowel transplantation is compatible with a normal nutritional status, when no rejection is involved. Transplantation in the histoincompatible WAG-to-BN combination without pretreatment resulted in rejection of the small bowel grafts in 16.6 +/- 2.7 days. Pretreatment with 3 BN blood transfusions to the WAG donor did not prolong the survival time; surprisingly, the transfusions induced a more-severe GVH reaction. Irradiation of the donor with 10 Gy was very effective in ameliorating the GVH disease, but the absence of the immunosuppressive effect of the GVH disease did lead to an accelerated graft rejection (7.5 +/- 0.9 days).