Studies on the Transplanted Heart. Role of Gamma-Globulin in Transplantation Immunity.

SummarySensitization of the recipient animal with spleen homogenate resulted in a significant increase in the serum gamma globulin fraction and subsequent accelerated rejection of the graft. In exceptional cases in which serum gamma-globulin level did not increase, the accelerated rejection was absent. Treatment with 6-MP reduced the gammaglobulin level and the grafts in these animals showed prolonged survival. Reduction of gamma-globulin by exchange transfusion failed to prolong survival time of the graft. These results are in accord with the view that humoral factors present in the gammaglobulin fraction play an important role in homograft rejection.