Cell-mediated lympholysis in H-2K/D identical congenic strain combinations.

Eight H-2K/D identical congenic strain combinations were tested in cell-mediated lympholysis. The reaction pattern of selected mouse strains revealed unidirectional reactivity to Tla-linked antigens in six strain combinations, whereas in two strain combinations the loci coding for the target antigen could only tentatively be linked to H-2. The Tla-linked loci defined by the different strain combinations appear to be identical with the H-2T (Qa-1) locus. Typing of B10.W lines for the H-2T (Qa-1) locus revealed the presence of alleles that appear to be the same as those present in inbred strains, as well as alleles that are different from the inbred-defined alleles but that share some determinants with the latter. The H-2T (Qa-1) system thus appears to consist of a limited number of alleles, some of which are closely related and presumably similar in their genetic structure.