title: Evidence of HLA-DR antigen biosynthesis by human keratinocytes in disease.
abstract: As opposed to normal human skin where HLA-DR expression is restricted to the Langerhans cell (LC) population, HLA-DR, but not HLA-DS antigens can be readily detected on keratinocytes (KC) in certain disease states, i.e., cutaneous T cell lymphoma (CTCL), graft-vs-host disease (GVHD), and lichen planus (LP). To clarify the cellular origin of KC-bound HLA-DR antigens, we used a monoclonal antibody directed against determinants solely expressed on the cytoplasmic HLA-DR gamma chain (VIC-Y1) and observed that, by immunofluorescence, KC displaying HLA-DR alpha/beta complexes on their surface uniformly displayed cytoplasmic VIC-Y1 reactivity. In view of the crucial role of the gamma chain for HLA-DR biosynthesis, we conclude that HLA-DR antigens on KC are actively synthesized by these cells.
mesh_terms: D004817:Epidermis / Q000276:immunology*; D005455:Fluorescent Antibody Technique; D006086:Graft vs Host Disease / Q000150:complications; D006684:HLA-DR Antigens; D000949:Histocompatibility Antigens Class II / Q000032:analysis*; D006801:Humans; D007633:Keratins / Q000378:metabolism*; D008010:Lichen Planus / Q000276:immunology; D008223:Lymphoma / Q000150:complications; D012871:Skin Diseases / Q000209:etiology / Q000276:immunology*; D013601:T-Lymphocytes
chemical_list: D006684:HLA-DR Antigens; D000949:Histocompatibility Antigens Class II; D007633:Keratins