title: Accessory function of thymic and tonsillar dendritic cells in interferon gamma production by T lymphocytes.
abstract: Human dendritic cells (DC) were purified from tonsils and thymus by a three-step procedure. Over 85% of cells in the purified DC preparations were identified as DC based on their characteristic morphology, presence of HLA-DR, Pro-Iml and Pro-Im2 antigens, and absence of macrophage associated antigens OKM1 and OKM5. To study the accessory function of DC in IFN-gamma production, T lymphocytes and T4+ or T8+ subsets were purified from peripheral blood and tonsils. Addition of autologous or allogeneic tonsillar DC to cultures of purified T cells caused up to a fifteen-fold increase in phytohemagglutinin (PHA)-induced IFN-gamma production and up to a seven-fold augmentation of IFN-gamma induction by interleukin 2 (IL 2). Thymic DC also showed a similar potent accessory activity on IFN-gamma production with concanavalin A (Con A) or PHA. Marked enhancement of IFN-gamma production by T cells was seen in the presence of as little as 0.3% thymic DC.
mesh_terms: D000911:Antibodies, Monoclonal; D002478:Cells, Cultured; D006684:HLA-DR Antigens; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism*; D008211:Lymphocyte Cooperation; D008221:Lymphoid Tissue / Q000166:cytology* / Q000276:immunology; D014066:Palatine Tonsil / Q000166:cytology* / Q000276:immunology / Q000502:physiology; D013601:T-Lymphocytes / Q000378:metabolism*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology / Q000378:metabolism; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology / Q000378:metabolism; D013950:Thymus Gland / Q000166:cytology* / Q000276:immunology / Q000502:physiology
chemical_list: D000911:Antibodies, Monoclonal; D006684:HLA-DR Antigens; D000949:Histocompatibility Antigens Class II; D007371:Interferon-gamma