title: HLA-DR expression in human fetal intestinal epithelium.
abstract: Villus epithelial cells in fetal human small intestine are HLA-DR- until 17 weeks gestation. At 18 weeks HLA-DR begins to be expressed in the epithelial cells, usually at the villus tips. Of 13 specimens examined between 18 and 22 weeks gestation, two were HLD-DR-, seven had HLA-DR expressed only at the villus tips and in four most of the villus epithelial cells were HLA-DR+. The epithelium overlying the Peyer's patches in fetal intestine was also HLA-DR+. T cells in explant cultures of fetal intestine were activated in situ using pokeweed mitogen. The local cell mediated immune reaction increased expression of HLA-DR on the villus and crypt epithelial cells. Organ culture supernatants from explants treated with pokeweed mitogen induced HLA-DR expression on the HT-29 epithelial cell line; an effect inhibited by antibody against human interferon gamma.
mesh_terms: D004848:Epithelium / Q000276:immunology; D005865:Gestational Age; D006684:HLA-DR Antigens / Q000032:analysis*; D006801:Humans; D007124:Immunoenzyme Techniques; D007371:Interferon-gamma / Q000494:pharmacology; D007421:Intestine, Small / Q000196:embryology / Q000276:immunology*; D009924:Organ Culture Techniques; D011994:Recombinant Proteins; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D006684:HLA-DR Antigens; D011994:Recombinant Proteins; D007371:Interferon-gamma