title: The production of IFN-gamma by IL-12/IL-18-activated macrophages requires STAT4 signaling and is inhibited by IL-4.
abstract: Macrophages release IFN-gamma on combined stimulation with IL-12 and IL-18, but the signaling requirements of this process and its regulation by other cytokines are unknown. Here, we demonstrate that STAT4 is indispensable for IL-12/IL-18-induced production of IFN-gamma by mouse peritoneal macrophages. Type 2 NO synthase (NOS2), which we previously found to be a prerequisite for IL-12-induced IFN-gamma production in NK cells, was not required for IFN-gamma production by these macrophages. IL-12 alone already induced the expression of IFN-gamma mRNA, but nuclear translocation of STAT4, the release of IFN-gamma protein, and the subsequent production of NO was strictly dependent on the simultaneous presence of IL-18. NF-kappa B, which mediates IL-18 effects in T cells, was only weakly activated by IL-12 and/or IL-18 in macrophages. Known inhibitors of macrophage functions (e.g., IL-4 and TGF-beta) also suppressed macrophage IFN-gamma production and the subsequent production of NOS2-derived NO. The inhibitory effect of IL-4 was paralleled by nuclear translocation of STAT6, which in EMSAs was able to bind to the same DNA oligonucleotide as STAT4. These results further define the production of IFN-gamma by macrophages and point to a diversity in the signals required for IFN-gamma production by various cell types.
authors.affiliation: Institute of Clinical Microbiology, Immunology, and Hygiene, University of Erlangen, Erlangen, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Schindler
authors.forename: M B
authors.initials: MB
authors.lastname: Lutz
authors.forename: M
authors.initials: M
authors.lastname: Röllinghoff
authors.forename: C
authors.initials: C
authors.lastname: Bogdan
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000235:genetics / Q000276:immunology; D000818:Animals; D001202:Ascitic Fluid / Q000276:immunology; D001667:Binding, Competitive / Q000235:genetics / Q000276:immunology; D002478:Cells, Cultured; D004268:DNA-Binding Proteins / Q000172:deficiency / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D004357:Drug Synergism; D005260:Female; D007369:Interferon Inducers / Q000494:pharmacology; D007371:Interferon-gamma / Q000037:antagonists & inhibitors* / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D018664:Interleukin-12 / Q000378:metabolism / Q000502:physiology*; D020382:Interleukin-18 / Q000378:metabolism / Q000502:physiology*; D053727:Interleukin-18 Receptor alpha Subunit; D015847:Interleukin-4 / Q000502:physiology*; D008262:Macrophage Activation; D017737:Macrophages, Peritoneal / Q000201:enzymology / Q000276:immunology* / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D016328:NF-kappa B / Q000378:metabolism; D009569:Nitric Oxide / Q000096:biosynthesis; D019001:Nitric Oxide Synthase / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology; D052247:Nitric Oxide Synthase Type II; D009841:Oligonucleotides / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis; D018123:Receptors, Interleukin / Q000096:biosynthesis / Q000235:genetics; D053707:Receptors, Interleukin-12; D053724:Receptors, Interleukin-18; D050797:STAT4 Transcription Factor; D050800:STAT6 Transcription Factor; D015398:Signal Transduction / Q000235:genetics / Q000276:immunology*; D015534:Trans-Activators / Q000172:deficiency / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
chemical_list: D004268:DNA-Binding Proteins; C508573:Il18r1 protein, mouse; D007369:Interferon Inducers; D020382:Interleukin-18; D053727:Interleukin-18 Receptor alpha Subunit; D016328:NF-kappa B; D009841:Oligonucleotides; D012333:RNA, Messenger; D018123:Receptors, Interleukin; D053707:Receptors, Interleukin-12; D053724:Receptors, Interleukin-18; D050797:STAT4 Transcription Factor; D050800:STAT6 Transcription Factor; C494091:Stat4 protein, mouse; C494100:Stat6 protein, mouse; D015534:Trans-Activators; D018664:Interleukin-12; D015847:Interleukin-4; D009569:Nitric Oxide; D007371:Interferon-gamma; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse