Studies of the enhancement of natural cytotoxicity by the streptococcal immunopotentiator OK432.
The immunopotentiator OK432, a product of Streptococcus pyogenes A3, enhanced the natural killer (NK) activity of unseparated human peripheral blood mononuclear cells (PBM) and separated, nonadherent lymphocytes (PBL) containing less than 0.5% contamination with monocytes. Following treatment with OK432, both unseparated and non-adherent cell preparations produced interferon (IFN) alpha and gamma and low levels of interleukin-2 (IL-2). However, in the presence of neutralising amounts of anti-IFN alpha and gamma antisera, the NK enhancing effect of OK432 was not fully inhibited. Filtered supernatants derived from OK432-treated PBM or PBL also enhanced the NK activity of fresh PBM. In this instance, in most experiments, the NK enhancing effect of supernatants (from non-adherent cells) was fully inhibited by anti-IFN antisera. However, in some experiments, enhancement of NK activity by anti-IFN antisera-treated supernatants was still found. It is suggested that the presence of IL-2 or, possibly, other as yet uncharacterized factors secreted following OK432 treatment, account for this residual enhancement of NK activity.
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Christmas
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Meager
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Moore
D000906:Antibodies / Q000494:pharmacology; D001688:Biological Products / Q000494:pharmacology*; D002469:Cell Separation; D002474:Cell-Free System / Q000187:drug effects; D003602:Cytotoxicity, Immunologic / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007372:Interferons / Q000096:biosynthesis / Q000276:immunology; D007376:Interleukin-2 / Q000008:administration & dosage / Q000032:analysis / Q000096:biosynthesis; D008213:Lymphocyte Activation / Q000187:drug effects; D008214:Lymphocytes / Q000145:classification / Q000187:drug effects / Q000276:immunology*; D009000:Monocytes / Q000276:immunology; D010844:Picibanil / Q000494:pharmacology*
D000906:Antibodies; D001688:Biological Products; D007376:Interleukin-2; D010844:Picibanil; D007372:Interferons