title: Suppression of the effector phase of inflammatory arthritis by double-stranded RNA is mediated by type I IFNs.
abstract: Innate immune receptors that recognize nucleic acids, such as TLRs and RNA helicases, are potent activators of innate immunity that have been implicated in the induction and exacerbation of autoimmunity and inflammatory arthritis. Polyriboinosine-polyribocytidylic acid sodium salt (poly(IC)) is a mimic of dsRNA and viral infection that activates TLR3 and the RNA helicases retinoic acid-induced gene-1 and melanoma differentiation-associated gene-5, and strongly induces type I IFN production. We analyzed the effects of systemic delivery of poly(IC) on the inflammatory effector phase of arthritis using the collagen Ab-induced and KRN TCR-transgenic mouse serum-induced models of immune complex-mediated experimental arthritis. Surprisingly, poly(IC) suppressed arthritis, and suppression was dependent on type I IFNs that inhibited synovial cell proliferation and inflammatory cytokine production. Administration of exogenous type I IFNs was sufficient to suppress arthritis. These results suggest a regulatory role for innate immune receptors for dsRNA in modulating inflammatory arthritis and provide additional support for an anti-inflammatory function of type I IFNs in arthritis that directly contrasts with a pathogenic role in promoting autoimmunity in systemic lupus.
authors.affiliation: Arthritis and Tissue Degeneration Program, Hospital for Special Surgery, New York, NY 10021, USA.
authors.forename: Anna
authors.initials: A
authors.lastname: Yarilina
authors.forename: Edward
authors.initials: E
authors.lastname: DiCarlo
authors.forename: Lionel B
authors.initials: LB
authors.lastname: Ivashkiv
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000276:immunology / Q000494:pharmacology; D001169:Arthritis, Experimental / Q000188:drug therapy / Q000276:immunology* / Q000473:pathology; D001172:Arthritis, Rheumatoid / Q000188:drug therapy / Q000276:immunology* / Q000473:pathology; D015551:Autoimmunity / Q000187:drug effects; D007113:Immunity, Innate / Q000187:drug effects; D007249:Inflammation / Q000276:immunology / Q000473:pathology; D007369:Interferon Inducers / Q000276:immunology / Q000494:pharmacology*; D007370:Interferon Type I / Q000276:immunology* / Q000494:pharmacology; D008180:Lupus Erythematosus, Systemic / Q000276:immunology / Q000473:pathology; D051379:Mice; D016688:Mice, Inbred NOD; D011070:Poly I-C / Q000276:immunology / Q000494:pharmacology*; D020365:RNA Helicases / Q000276:immunology; D012330:RNA, Double-Stranded / Q000276:immunology / Q000494:pharmacology*; D051196:Toll-Like Receptor 3 / Q000276:immunology; D014777:Virus Diseases / Q000276:immunology / Q000473:pathology
chemical_list: D000998:Antiviral Agents; D007369:Interferon Inducers; D007370:Interferon Type I; D012330:RNA, Double-Stranded; D051196:Toll-Like Receptor 3; D020365:RNA Helicases; D011070:Poly I-C