H-2 antigen variants in a cultured heterozygous mouse leukemia cell line

Abstract

An H-2 antigen variant, referred to as −4 + 31 clone 1, was selected by its resistance to an anti-H-2Dd antiserum (BALB.G anti-BALB/c.H-2 g antiH-2 d ). When tested by cell-mediated cytolysis, this variant was found to be sensitive to cytolytic T lymphocytes raised in the same donor-host combination as that used in raising the antiserum. Further CML characterization of this variant, reported here, indicates that the cell line is in fact resistant to anti-H-2Dd killer cells raised in a more restricted immunization, viz. BALB.G anti-BALB/cH-2 db ,H-2 g anti-H-2 db . It is, however, sensitive to cytolytic cells raised in (BALB.B xBALB/c-H-2db) F1 H-2 b /H-2 db ) against the BALB/c strain. These results suggest that the variant does not express H-2Dd itself, but probably expresses CML target antigens that are missing in theH-2 db mutation. This in vitro-isolated variant might thus be the complementary mutation to the in vivoobtainedH-2 db mutation.