title: Expression of cell-surface HLA-DR, HLA-ABC and glycophorin during erythroid differentiation.
abstract: The unexpected discovery that Ia-like (HLA-DR) antigens in humans were present on blast cells from acute myeloblastic leukaemia led to the finding that normal granulocytic progenitors, in contrast to their mature descendents, also expressed HLA-DR antigens. Thus, anti-Ia sera stain a proportion of myeloblasts in normal bone marrow, inhibit myeloid progenitor (CFU-GM) colony formation in the presence of complement and can be used to label and separate CFU-GM on a fluorescence-activated cell sorter (FACS). Winchester et al. subsequently reported that erythroid progenitors (BFU-E and CFU-E) were also inhibited or killed by anti-Ia (p28,37) and complement. These observations raised the possibility that HLA-DR (or presumptive I-region equivalent) products might have a regulatory role in early haematopoiesis. We have now analysed HLA-DR and HLA-ABC antigen expression on normal erythroid progenitors using monoclonal antibodies to non-polymorphic determinants and fluorescence-activated cell sorting. In parallel experiments, we tested a monoclonal antibody to glycophorin, a well defined  erythroid-specific cell-surface membrane glycoprotein. We report that HLA-DR, HLA-ABC and glycophorin are all expressed at various stages during erythroid differentiation.
mesh_terms: D001853:Bone Marrow / Q000276:immunology; D002999:Clone Cells / Q000276:immunology; D000939:Epitopes; D004900:Erythroblasts / Q000276:immunology*; D004912:Erythrocytes / Q000276:immunology*; D004920:Erythropoiesis; D006021:Glycophorins / Q000276:immunology / Q000378:metabolism*; D006680:HLA Antigens / Q000032:analysis*; D000949:Histocompatibility Antigens Class II / Q000032:analysis*; D006801:Humans; D012795:Sialoglycoproteins / Q000378:metabolism*; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D000939:Epitopes; D006021:Glycophorins; D006680:HLA Antigens; D000949:Histocompatibility Antigens Class II; D012795:Sialoglycoproteins