title: The detection of two serologically distinct HLA-A28 specificities.
abstract: We describe a serum, 9045, that detects a subset of A28 bearing cells in a mixed population of American blacks, Caucasians of Jewish ancestry and non-Jewish Caucasians. The serum reacts preferentially with A28 positive cells from American Blacks and Jewish Caucasians and does not react with non-Jewish Caucasians. This new specificity, referred to as A28.2, is strongly associated with HLA-B14. In contrast, A28 positive but 9045 negative cells (referred to as A28.1) do not show this association. The A28-2 determinants appears to be antigenically similar to the A28.1 determinant, but distinct from the public antigenic determinants shared by A28, A2, A9 and by A28, Aw33, Aw34 and A26. Based upon this analysis, we conclude that HLA-A28, as defined by most A28 antisera, comprises at least two populations of molecules. The A28.2 form may have arisen in the Mediterranean basin region, whereas the A28.1 form seems to be more prevalent in non-Jewish Caucasians of Northern European ancestry.
mesh_terms: D000042:Absorption; D044383:Black People; D000939:Epitopes; D006680:HLA Antigens / Q000235:genetics / Q000276:immunology*; D006650:Histocompatibility Testing; D006801:Humans; D007106:Immune Sera / Q000276:immunology; D007585:Jews; D044465:White People
chemical_list: D000939:Epitopes; D006680:HLA Antigens; D007106:Immune Sera