title: Cytotoxic T lymphocytes: blocked differentiation at the 'poised' stage.
abstract: The effect of different concentrations of phorbol myristate acetate (PMA) on the development of cytotoxic cells was studied. PMA was selectively able to prevent the development of cytotoxic cells in a mixed leucocyte culture, while allowing the responding cells to proliferate. The higher concentration of PMA (10(-5)M) blocked both direct cytotoxicity and lytic activity in the presence of lectin, while the lower concentration (10(-8) M) only prevented direct lytic function. The removal of PMA and subsequent addition of recombinant interleukin 2 (IL-2) or IL-2-containing supernatants effectively reversed the effect of PMA with recovery of antigen-specific lytic function of cells treated with 10(-8) M, while cells treated with 10(-5)M PMA only recovered lectin-dependent cytotoxic ability.
mesh_terms: D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology; D007959:Lymphocyte Culture Test, Mixed; D013602:T-Lymphocytes, Cytotoxic / Q000187:drug effects*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface; D007376:Interleukin-2; D013755:Tetradecanoylphorbol Acetate