title: HLA class I antigen (heavy and light chain) expression by Langerhans cells and keratinocytes of the normal human epidermis: ultrastructural quantitation using immunogold labelling procedure.
abstract: Using an immunogold labelling procedure, we quantified the density of major histocompatibility (MHC) class I antigens on the surface of Langerhans cells (LCs) and keratinocytes of the normal human epidermis. According to ultrastructural features, keratinocytes were divided into three subpopulations: stratum basalis (SBK), stratum spinosum (SSK), and stratum granulosum keratinocytes (SGK), and analyzed separately. For this purpose, three monoclonal antibodies (MCAs) were employed: an anti-HLA A,B,C, and anti-B2-microglobulin (B2-m), and a polymorphic anti-HLA A2 Aw69 MCA. Under electron microscopy, quantitative analysis demonstrated: (a) the presence of a high amount of HLA monomorphic determinants on SBK and SSK and moderate but significant labelling of SGK; (b) the very weak density of MHC class I antigens on the surface of epidermal LCs; (c) the expression, at an identical level, of the HLA heavy chain common determinant (HLA A,B,C), B2-m, and the alloantigen HLA A2 by all epidermal cells (ECs) apart from SGKs and LCs that presented far fewer HLA A2 sites than monomorphic determinants (B2-m and HLA A,B,C); (d) the absence of HLA class I on corneocytes and a moderate labelling of melanocytes. A knowledge of the precise quantitative distribution of HLA class I antigens among various cell subpopulations of the normal human epidermis would be very useful for the study and follow-up of cutaneous malignancies that are known to lose these molecules as well as for the understanding of immune responses, especially allospecific, that involve the skin.
authors.affiliation: INSERM U209, Hôpital E. Herriot, Lyon, France.
authors.forename: V
authors.initials: V
authors.lastname: Gielen
authors.forename: D
authors.initials: D
authors.lastname: Schmitt
authors.forename: J
authors.initials: J
authors.lastname: Thivolet
mesh_terms: D000078404:Epidermal Cells; D004817:Epidermis / Q000276:immunology*; D005455:Fluorescent Antibody Technique; D006680:HLA Antigens / Q000032:analysis*; D006801:Humans; D007150:Immunohistochemistry; D007801:Langerhans Cells / Q000276:immunology* / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D006680:HLA Antigens