Cell-mediated cytotoxicity to non-MHC alloantigens on mouse epidermal cells - VI. Influence of the MHC on the tissue specificity of cytotoxic T-lymphocyte responses

Mice of the C3H/He and A non-H-2 backgrounds are disparate from mice of the B10 background for the tissue-restricted, non-H-2 alloantigen of epidermal cells (EC), Epa-1, that is expressed by EC but not by lymphocytes (LC), as well as for a number of other alloantigens of the B10 background that are expressed by both EC and LC, generically referred to as "lymphocyte/epidermal alloantigens" (LEA). In this study, we compared the ability of various H-2 congenic strains on the C3H or A backgrounds to mount cytotoxic T-lymphocyte (CTL) responses to EC from H-2 compatible mice of the B10 background. High responses to Epa-1 were detected only in the H-2^aand H-2^khaplotypes; H-2^b, H-2^o1, H-2^s, H-2^t1, and H-2^t2 haplotypes were nonresponders to Epa-1. High responses to LEA were detected in H-2^a, H-2^b, H-2^s, H-2^t1, and H-2^t2 haplotypes; H-2^kand H-2^o1 were nonresponsive to LEA. Analysis of the H-2K, I and D region alleles of responders indicates that H-2K^kis essential for anti-Epa CTL responses, whereas D^d, D^b, or K^swere all permissive for strong anti-LEA responses. The ability to mount a given CTL response was not associated with differences in I-region alleles. These results are discussed in terms of K/D region products serving as Ir-gene products for CTL and in determining the apparent tissue-specificity of CTL.