Graft versus Host Reaction modified by in vitro Marrow–Erythrocyte Preincubation

Abstract

SPECIFIC skin allograft tolerance has been induced in 94 per cent of lethally irradiated AKR recipients by transplantation of AKR marrow preincubated in vitro with washed allogeneic erythrocytes for 35 min at 25°–26° C¹. It was suggested that tolerance resulted from a failure of preincubated marrow to recognize the erythrocyte–donor strain as foreign². The marrow cells were able to distinguish between erythrocytes of reciprocal hybrids, but not between the parental strains and the hybrid in which the female strain used in the hybrid cross was identical inbred strains³. The functional capacity of the marrow stem cells was altered; however, this modification did not affect the protective capacity of the marrow. This was the principal difference between the in vitro incubation method of inducing skin allograft tolerance and the neonatal induction of tolerance in marrow donors². The marrow–erythrocyte preincubation method was used to determine whether this method of modifying the ability of the marrow to recognize and respond to tissue antigens would alter the lethal effects of the graft versus host reaction.