title: In vitro potentiation of human natural killer cell activity by a streptococcal preparation, OK-432: interferon and interleukin-2 participation in the stimulation with OK-432.
abstract: Inasmuch as human natural killer (NK) cell activity was markedly augmented by a streptococcal immunopotentiator, OK-432, both in vivo and in vitro, the mechanism in which OK-432 augmented human NK cell activity was analyzed. Culture supernatants of nonadherent lymphocytes stimulated with OK-432 significantly augmented NK cell activity. Significant activity of both interferon (IFN) (both alpha- and gamma-types) and interleukin-2 (IL-2) was detected in the culture supernatants from nonadherent lymphocytes. Concomitant treatment of supernatants with anti-IFN-alpha antiserum and pH-2 glycine-HCI buffer or the absorption of supernatants with an IL-2-dependent cell line completely abrogated the NK-augmenting activity, whereas the treatment with either one of these resulted in only partial elimination of the activity. These results indicate that OK-432 stimulates human nonadherent lymphocytes to produce IFN and IL-2 and that both factors are primarily responsible for the NK augmentation by OK-432.
mesh_terms: D001688:Biological Products / Q000494:pharmacology*; D002448:Cell Adhesion; D002478:Cells, Cultured; D003602:Cytotoxicity, Immunologic; D006801:Humans; D007372:Interferons / Q000096:biosynthesis / Q000276:immunology; D007376:Interleukin-2 / Q000096:biosynthesis / Q000276:immunology; D007694:Killer Cells, Natural / Q000276:immunology*; D008213:Lymphocyte Activation; D010844:Picibanil / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D013205:Staphylococcal Protein A / Q000494:pharmacology
chemical_list: D001688:Biological Products; D007376:Interleukin-2; D013205:Staphylococcal Protein A; D010844:Picibanil; D007372:Interferons