title: Amnion membrane epithelial cells express class I HLA and contain class I HLA mRNA.
abstract: Amnion epithelial cells in membranes from term deliveries, which have been reported not to express histocompatibility Ag, were evaluated for HLA by using an avidin-biotin immunoperoxidase staining system and for class I HLA mRNA by Northern blotting and in situ hybridization. There were three major findings from these studies. 1) Amnion cells frequently expressed class I HLA. Three mAb to monomorphic determinants of class I HLA were used: 61D2, PA2.6, and W6/32. 61D2 identified 1 of 8 fresh amnion membranes as class I positive whereas PA2.6 identified 4/8 and W6/32 identified 5/8. 2) Amnion cells contained class I HLA mRNA. RNA extracted from amnion membranes hybridized to a class I HLA probe (pHLA1.1) in Northern blotting. In situ hybridization procedures with pHLA1.1 showed that essentially all amnion cells contained class I HLA mRNA. 3) Levels of class I HLA mRNA in amnion cells could be modulated. Exposure of amnion explants to medium containing IFN-gamma enhanced levels of class I HLA mRNA in amnion cells, whereas epidermal growth factor diminished those levels. The results suggest that amnion cells transcribe class I HLA genes and are capable of synthesizing class I H chains but that expression may be modulated by extrinsic regulatory molecules.
mesh_terms: D000650:Amnion / Q000187:drug effects / Q000276:immunology*; D002478:Cells, Cultured; D004815:Epidermal Growth Factor / Q000494:pharmacology; D004848:Epithelium / Q000187:drug effects / Q000276:immunology; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects; D006680:HLA Antigens / Q000032:analysis*; D006801:Humans; D007124:Immunoenzyme Techniques; D007371:Interferon-gamma / Q000494:pharmacology; D009693:Nucleic Acid Hybridization; D011247:Pregnancy; D012333:RNA, Messenger / Q000032:analysis*
chemical_list: D006680:HLA Antigens; D012333:RNA, Messenger; D004815:Epidermal Growth Factor; D007371:Interferon-gamma