HLA-DR2 and DR4 further defined by two new HLA-D specificities (HTC) derived from Israeli Jewish donors: comparative study in Caucasian, Korean, Eskimo and Israeli populations.

Two newly-identified HLA-D antigens were characterized by testing selected homozygous typing cells (HTC) against responder panels derived from Caucasian, Korean, Alaskan Eskimo and Israeli Jewish populations. The first specificity, defined by typing cell "AZH", is associated with DR2 haplotypes and is detected primarily in Israelis. The second specificity, defined by HTC "TAS", is associated with DR4 haplotypes and is detected with relatively high frequency in Koreans and Alaskan Eskimos. The data indicate that HTC-AZH and -TAS can be used to identify previously undefined splits or variants of lymphocyte-defined (LD) determinants associated with DR2 and DR4 haplotypes. Further, the study demonstrates the utility of comparative population analysis in identifying and characterizing alleles encoded by the HLA-D region and provides additional evidence of heterogeneity within the family of serologically-defined HLA-DR haplotypes.