title: Cultured human thymus epithelial monolayer cells induce CD4 expression on mononuclear cells of AIDS patients in vitro.
abstract: We investigated the in vitro effect of cultured human thymic epithelial monolayer cells on mononuclear cells (MNC) from patients with Acquired Immune Deficiency Syndrome (AIDS) and AIDS-related complex (ARC). Patients having undergone bone-marrow transplantation (BMT), who showed a similar deficiency of T-lymphocytes expressing CD4 (Leu-3, T4), and healthy blood donors served as controls. Most epithelial monolayer cells were of thymic medulla origin, as documented using a panel of monoclonal antibodies to thymic epithelial cells. In AIDS/ARC patients the CD4-positive cells (ranging between 4 and 30% of MNC) increased by a factor of 1.56 (s.e.m. 0.15, n = 12) during a 2 h incubation on the monolayer. Human fetal lung fibroblasts were inactive in this respect. There was no consistent change in cells expressing CD3 (Leu-4, T3), CD5 (Leu-1) or CD8 (Leu-2, T8). In BMT patients and healthy controls, neither thymus epithelium nor fibroblasts had any effect on T cell marker expression. Incorporation of tritiated thymidine by stimulated or unstimulated lymphocytes was increased after incubation for 3 days on either epithelium or fibroblasts. We conclude that CD4 expression is induced on MNC from AIDS/ARC patients during a 2 h incubation on epithelial monolayers.
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000276:immunology*; D000328:Adult; D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface / Q000032:analysis*; D002478:Cells, Cultured; D004848:Epithelium / Q000276:immunology; D005347:Fibroblasts / Q000276:immunology; D006801:Humans; D007962:Leukocytes / Q000276:immunology*; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D013601:T-Lymphocytes / Q000276:immunology; D013950:Thymus Gland / Q000276:immunology*
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface