SUPPRESSION OF GRAFT-VERSUS-HOST DISEASE AND ANTIBODY FORMATION BY PHYTOHEMAGGLUTININ

Abstract

SUMMARY Phytohemagglutinin (PHA) has been used to suppress both graftversus- host disease and antibody formation in mice. However, PHA heated at 100 C for 30 min to destroy its in vitro mitogenicity and certain antigens produced quantitatively similar suppression. Consequently, the immunosuppressive effects of PHA demonstrated in our experiments were unrelated to its in vitro mitogenicity and are probably results of antigen competition