title: Pattern of expression of HLA-DR and HLA-DQ antigens and mRNA in myeloid differentiation.
abstract: We examined the expression of HLA-DR and HLA-DQ antigens and mRNA from myeloid and lymphoid cells obtained from normal volunteers and established cell lines. Cytofluorometric analysis and immunoprecipitation were performed using murine monoclonal antibodies specific for HLA-DR (L-243) and HLA-DQ (Leu 10). The expression of mRNA for HLA-DR and HLA-DQ chains was determined by Northern blot and RNA dot-blot analysis. Lymphoid cell lines expressed both HLA-DR and HLA-DQ antigens, with consistently higher levels of expression of DR. Myeloid cell lines of early myeloblast or bipotent (myeloid-erythroid) phenotype (KG-1, KG-1a, HEL) expressed HLA-DR at high levels, whereas cell lines manifesting a greater degree of myeloid maturation (ML-3, HL-60, U937) expressed DR at low or undetectable levels. The HLA-DQ antigen was expressed at low levels on the surface of KG-1 and KG-1a cells but was not detectable on other myeloid cell lines. The expression of mRNA for HLA-DR and HLA-DQ chains paralleled the pattern of expression of the respective antigens. The HL-60 and U-937 cells stimulated to differentiate in vitro to macrophages with 1,25 dihydroxyvitamin D3 [1,25(OH)2D3] were induced to express detectable levels of HLA-DR antigens. Exposure to gamma-interferon (gamma-IFN) increased the expression of HLA-DR antigens by all myeloid cell lines. Induction of differentiation in vitro with either 1,25(OH)2D3 or dimethyl sulfoxide potentiated this effect of gamma-IFN. Expression of the HLA-DQ antigens was increased on KG-1 myeloblasts after exposure to gamma-IFN. HLA-DQ expression could not be detected on other myeloid cell lines after exposure to gamma-IFN, nor was HLA-DQ expression stimulated by gamma-IFN after HL-60 and U-937 cells were induced to differentiate to macrophagelike cells in vitro. These results provide additional evidence that expression of the HLA-DR and HLA-DQ genes may be independently regulated in human myeloid cells.
mesh_terms: D002117:Calcitriol / Q000494:pharmacology; D002454:Cell Differentiation; D002460:Cell Line; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D005455:Fluorescent Antibody Technique; D005786:Gene Expression Regulation; D006681:HLA-D Antigens / Q000276:immunology*; D006683:HLA-DQ Antigens / Q000235:genetics / Q000276:immunology*; D006684:HLA-DR Antigens / Q000235:genetics / Q000276:immunology*; D006412:Hematopoietic Stem Cells / Q000276:immunology* / Q000502:physiology; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D008214:Lymphocytes / Q000502:physiology*; D012333:RNA, Messenger / Q000235:genetics
chemical_list: D006681:HLA-D Antigens; D006683:HLA-DQ Antigens; D006684:HLA-DR Antigens; D012333:RNA, Messenger; D007371:Interferon-gamma; D002117:Calcitriol; D004121:Dimethyl Sulfoxide