title: Requirement of Ia-positive accessory cells for T-cell stimulation with 12-O-tetradecanoyl-phorbol-13-acetate.
abstract: The cellular mechanism of lymphocyte stimulation with 12-O-tetradecanoyl-phorbol-13-acetate (TPA) was studied using mouse spleen cells. TPA had a potent mitogenic activity on mouse spleen cells at concentrations of 10-1000 ng/ml. The maximum response was observed on Day 2. Other phorbol derivatives such as phorbol, phorbol-12-monomyristate, and phorbol-13-monoacetate had no mitogenic activity. The responder cells in the stimulation experiment with TPA were Thy-1-positive T cells. Nylon column purification of spleen cells diminished the response to TPA, but the addition of spleen cells to nylon-purified T cells restored their responding activity, suggesting that the accessory cells were required for T-cell stimulation with TPA. The accessory cells were macrophage-like adherent cells and la-positive. The mechanism of T-cell stimulation with TPA was discussed from the standpoint of the requirement of two different stimulatory signals.
mesh_terms: D000818:Animals; D000961:Antilymphocyte Serum / Q000494:pharmacology; D004306:Dose-Response Relationship, Immunologic; D005260:Female; D000949:Histocompatibility Antigens Class II / Q000032:analysis; D007700:Kinetics; D008213:Lymphocyte Activation / Q000187:drug effects*; D008211:Lymphocyte Cooperation; D008264:Macrophages / Q000276:immunology*; D008297:Male; D051379:Mice; D008805:Mice, Inbred A; D008809:Mice, Inbred C3H; D010704:Phorbols / Q000494:pharmacology*; D013601:T-Lymphocytes / Q000276:immunology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
chemical_list: D000961:Antilymphocyte Serum; D000949:Histocompatibility Antigens Class II; D010704:Phorbols; D013755:Tetradecanoylphorbol Acetate