title: Requirement for type 2 NO synthase for IL-12 signaling in innate immunity.
abstract: Interleukin-12 (IL-12) and type 2 NO synthase (NOS2) are crucial for defense against bacterial and parasitic pathogens, but their relationship in innate immunity is unknown. In the absence of NOS2 activity, IL-12 was unable to prevent spreading of Leishmania parasites, did not stimulate natural killer (NK) cells for cytotoxicity or interferon-gamma (IFN-gamma) release, and failed to activate Tyk2 kinase and to tyrosine phosphorylate Stat4 (the central signal transducer of IL-12) in NK cells. Activation of Tyk2 in NK cells by IFN-alpha/beta also required NOS2. Thus, NOS2-derived NO is a prerequisite for cytokine signaling and function in innate immunity.
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D006152:Cyclic GMP / Q000378:metabolism; D003602:Cytotoxicity, Immunologic; D004268:DNA-Binding Proteins / Q000378:metabolism; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D007113:Immunity, Innate; D007371:Interferon-gamma / Q000096:biosynthesis / Q000235:genetics; D007372:Interferons / Q000494:pharmacology; D018664:Interleukin-12 / Q000494:pharmacology / Q000502:physiology*; D053614:Janus Kinase 2; D007694:Killer Cells, Natural / Q000276:immunology* / Q000378:metabolism; D018320:Leishmania major; D016773:Leishmaniasis, Cutaneous / Q000276:immunology* / Q000378:metabolism; D008239:Lysine / Q000031:analogs & derivatives / Q000494:pharmacology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D011518:Proto-Oncogene Proteins; D050797:STAT4 Transcription Factor; D015398:Signal Transduction; D053634:TYK2 Kinase; D015534:Trans-Activators / Q000378:metabolism; D015854:Up-Regulation