H-2 private specificity of in vivo-sensitized lymphocytes studied by adsorption on fibroblast monolayers.

Spleen cells or thymocytes immune to one H-2 genotype are cytotoxic to allogeneic target cells of a third-party genotype, provided the target shares private specificities determined by either the H-2K or the H-2D locus of the H-2 complex with the H-2 genotype used for sensitization in vivo. The present results on elimination of cytotoxicity to specificities determined by one of the H-2 loci after adsorption of the immune lymphoid cells onto fibroblasts bearing this specificity suggest a state of diversity among effector lymphocytes reactive to the antigens determined by either the H-2K or the H-2D locus of the H-2 complex. Thymus cells activated in vivo were less specifically adsorbable than spleen cells of tumor-allografted mice.