Endothelial monocyte antigens are coded for by loci centromeric of HLA-B.
900 pregnancy sera were screened for monocyte antibodies. 23 sera (2.6%) were found to be reactive with monocytes in an allotypic pattern distinct from blood group ABO, HLA-A,B,C, DR and DQ specificities. Because of strong reactions and high reproducibility, 4 sera with pure endothelial monocyte (EM) reactivity and 2 sera also positive with B lymphocytes of certain donors were selected for population and family studies. The frequency of positive reactions in a panel of 26 random donors obtained with the pure EM sera was 13, 8, 8 and 13% with clearly distinct patterns. Analysis of the tentatively designated EM antigens 1.1, 1.2, 2.1, and 2.2 in 7 families revealed definite segregation with HLA. By means of two crossing-over events within the HLA region the two hypothetical EM loci were localized centromeric of HLA-A and one of both loci centromeric of HLA-B.
D000954:Antigens, Surface / Q000235:genetics*; D002906:Chromosomes, Human, 6-12 and X; D004727:Endothelium / Q000166:cytology; D005787:Gene Frequency; D008040:Genetic Linkage; D006680:HLA Antigens / Q000235:genetics*; D015234:HLA-A Antigens; D015235:HLA-B Antigens; D006801:Humans; D009000:Monocytes / Q000276:immunology*; D011995:Recombination, Genetic
D000954:Antigens, Surface; D006680:HLA Antigens; D015234:HLA-A Antigens; D015235:HLA-B Antigens