Transfer of specific immunosuppression of graft rejection using lymph from tolerant liver-grafted rats.

The effect on graft rejection of lymph from rats rendered tolerant of donor antigens by liver transplantation has been studied. Transfer, by daily intravenous injection, of lymph from PVG rats grafted with DA livers prolonged the survival of DA skin, kidney and heart grafts in normal PVG recipients. The effect was specific for the antigens of the liver donor. Suppression was short-term only; thus, after lymph injections were stopped, rejection occurred with a time course approximating a normal first-set reaction. The result suggests a reversible interference by materials in the tolerant lymph with early stages of sensitization of the recipients.