F1 HYBRID ANTI-PARENTAL H-2K CELL-MEDIATED LYMPHOLYSIS .1. STIMULATOR AND TARGET DETERMINANTS CONTROLLED BY THE H-2K REGION

Abstract

H-2k-heterozygous F1 hybrid mouse spleen cells cultured with irradiated H-2k-homozygous stimulator cells generated specific anti-parent cytolytic effectors. The parental antigenic determinants recognized by responder cells during induction (afferent arm) and by effector cells during cytolysis (efferent arm) were coded for, or regulated by, the H-2K-Hh-3 region of the MHC [major histocompatibility complex], according to recombinant analysis. There were no detectable influences by other linked or unlinked genes on the phenotypic expression of parental antigens; however, the anti-parent responsiveness was modulated by background genes of responder cells. The K end of H-2 controls determinants of F1 anti-parental H-2k CML [cell-mediated lympholysis] like the D end controls those of F1 anti-parental H-2b CML, thus confirming the basic symmetry of the H-2 complex. The relationship of this primary in vitro cell-mediated response with natural in vivo resistance to parental and allogeneic bone marrow grafts is discussed.