Abstract
Mixed lymphocyte culture (MLC) reactivity, induction of cytotoxicity in vitro, survival of skin allografts and induction of neonatal transplantation tolerance were compared in mice of the strain combinations differing in the entire H-2 complex or in individual segments of it. Antigenic products of the K end of the H-2 complex were more immunogenic and also more resistant to tolerance induction than the products of the D end of H-2. I-region products that elicited transplantation reactions of variable strength, depending on the detection system, were relatively easier to overcome in tolerance induction and could, at least in some combinations, contribute to tolerance induction across the barrier represented by the products of the K region of the H-2 complex.