Hyperacute rejection of skin allografts in the mouse. Sensitivity of ingrowing skin grafts to the action of alloantibody and rabbit complement.

The destructive action of alloantiserum and exogenous complement on ingrowing skin allografts was studied. B6AF1 recipients of a B10.D2 skin graft received a single intravenous injection of B6AF1 anti-B10.D2 serum (antiserum to H-2K.31) together with rabbit complement (RC) within the first 10 days after transplantation. Different models were used: recipients without immunosuppression, recipients treated with antilymphocyte serum, x-irradiation, or enhancing antibody. If the injection was given between day 5 and 10 after grafting, hyperacute rejection occurred in all cases. The rejection seemed to be most violent when the injection was given on days 7 or 8. Injections given on days 1, 2 or 3 after grafting could not induce hyperacute-rejection, but resulted, on the contrary, in a prolongation of graft survival, probably due to immunological enhancement. Injections on day 4 produced patchy necrosis, but the grafts recovered and the residual tissue showed a prolonged survival. The results suggest that the presence of a functioning vascular network is a prerequisite for the occurrence of hyperacute rejection of skin allografts in the mouse.