Destruction of Splenic Transplantation Antigens by a Factor Present in Liver

Abstract

Intact liver tissue implanted subcutaneously or liver cell suspensions injected subcutaneously sensitized recipient animals to subsequent appropriate skin grafts. Two standardized methods for the preparation of cell-free transplantation antigens, as assayed by accelerated skin graft rejection, were employed for the extraction of antigens from C57BL/6 spleen and liver. Both methods resulted in active sensitizing material from splenic tissue; however, no active antigen could be extracted from hepatic tissue. Incubation of active C57BL/6 splenic antigen for 1 hr at 37°C with C57BL/6 whole liver homogenate destroyed the ability of splenic antigen preparations to sensitize to subsequent skin grafts. Heating the whole liver homogenate to 80°C (10 min) prior to incubation destroyed the ability of the homogenate to inactivate the splenic antigen. Treatment of the liver homogenate with a chelating agent and dialysis of the liver homogenate failed to inhibit its ability to inactivate splenic antigen preparations. These experiments suggest that liver cells apparently contain a material which is capable of destroying the sensitizing ability of the transplantation antigens extracted from splenic tissue. These results further suggest an explanation for the frequently observed inability to prepare from hepatic tissue antigenic material capable of sensitizing to a subsequent skin allograft.