Generation of cytotoxic lymphocytes in mixed lymphocyte reactions II. Importance of private and public H-2 alloantigens on the expression of cytotoxicity

MLC were established to test for the generation of specific cytotoxic effector cells in CML. The target cell used to assay for CML in the five combinations tested was of a different H-2 haplotype from the stimulating cell population. Cytotoxicity was observed against this target only when it shared private alloantigens (antigens that are specific for the H-2D and H-2K region of different H-2 haplotypes) with the stimulating cell population. Very weak or no Cytotoxicity was found when such alloantigens were not shared, although cross-reactive public H-2 specificities were. These findings indicate that T cells display a cytotoxic potential against private H-2 antigens in a primary response in vitro and are not capable of responding to public H-2 specificities to the same level.