title: Human T-cell hybridomas producing lymphokines. II. Enhancement of lymphotoxin secretion from human T-cell hybridomas by phorbol myristate acetate.
abstract: Human lymphotoxin (LT)-producing T-cell hybridomas were constructed by fusing concanavalin A-activated human peripheral blood lymphocytes with emetine-actinomycin D-pretreated human acute lymphatic leukemia cells. LT secretion from these hybridomas was considerably enhanced by stimulation with phorbol-12-myristate-13-acetate (PMA) and concanavalin A or PMA alone. A study using cloned hybrid lines revealed that PMA/Con A acted directly on the LT-producing clones. Furthermore, PMA/Con A stimulated A-B9-24, one of the cloned hybridomas, and secreted fourfold larger amounts of LT under serum-free conditions than under serum-containing conditions. However, MIF/MAF and LT-producing cloned hybrid line E10-20 secreted rather decreased amounts of MIF/MAF when stimulated with PMA, while the LT secretion from the same hybridoma was enhanced with PMA.
mesh_terms: D002999:Clone Cells / Q000502:physiology; D003208:Concanavalin A / Q000494:pharmacology; D004306:Dose-Response Relationship, Immunologic; D006801:Humans; D006825:Hybridomas / Q000378:metabolism*; D007700:Kinetics; D008233:Lymphotoxin-alpha / Q000096:biosynthesis*; D008263:Macrophage Migration-Inhibitory Factors / Q000096:biosynthesis; D010641:Phenotype; D010704:Phorbols / Q000494:pharmacology*; D013601:T-Lymphocytes / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
chemical_list: D008233:Lymphotoxin-alpha; D008263:Macrophage Migration-Inhibitory Factors; D010704:Phorbols; D003208:Concanavalin A; D013755:Tetradecanoylphorbol Acetate