title: Interleukin-10 attenuation of collagen-induced arthritis is associated with suppression of interleukin-17 and retinoid-related orphan receptor γt production in macrophages and repression of classically activated macrophages.
abstract: BACKGROUND
  Our objective in the present study was to determine the signaling pathway of interleukin 10 (IL-10) for modulating IL-17 expression in macrophages and the importance of this mediation in collagen-induced arthritis (CIA).
  
  
  METHODS
  IL-10-knockout (IL-10⁻/⁻) mice and wild-type (WT) mice were immunized with chicken type II collagen (CII) to induce arthritis. The expression levels of IL-17 and retinoid-related orphan receptor γt (RORγt) in macrophages and joint tissues of IL-10⁻/⁻ and WT mice were analyzed by enzyme-linked immunosorbent assay, quantitative RT-PCR (qRT-PCR) and Western blotting. The F4/80 macrophages and positive IL-17-producing macrophages in synovial tissues of the mice were determined by immunohistochemistry. The populations of classically activated macrophage (M1) and alternatively activated macrophage (M2) phenotypes were analyzed by flow cytometry. The expression of genes associated with M1 and M2 markers was analyzed by qRT-PCR.
  
  
  RESULTS
  Compared to WT mice, IL-10⁻/⁻ mice had exacerbated CIA development, which was associated with increased production of T helper 17 cell (Th17)/Th1 proinflammatory cytokines and CII-specific immunoglobulin G2a antibody after CII immunization. Macrophages in IL-10⁻/⁻ mice had increased amounts of IL-17 and RORγt compared with the amounts in WT mice with CIA. Immunofluorescence microscopy showed that the number of IL-17-producing macrophages in synovial tissues was significantly higher in IL-10⁻/⁻ mice than in WT mice. IL-10 deficiency might promote macrophage polarization toward the proinflammatory M1 phenotype, which contributes to the rheumatoid arthritis inflammation response.
  
  
  CONCLUSIONS
  IL-10 inhibits IL-17 and RORγt expression in macrophages and suppresses macrophages toward the proinflammatory M1 phenotype, which is important for the role of IL-10 in mediating the pathogenesis of CIA.
authors.forename: Liang
authors.initials: L
authors.lastname: Ye
authors.forename: Zhongyang
authors.initials: Z
authors.lastname: Wen
authors.forename: Yanqun
authors.initials: Y
authors.lastname: Li
authors.forename: Bingni
authors.initials: B
authors.lastname: Chen
authors.forename: Ting
authors.initials: T
authors.lastname: Yu
authors.forename: Lanying
authors.initials: L
authors.lastname: Liu
authors.forename: Jinshun
authors.initials: J
authors.lastname: Zhang
authors.forename: Yanmei
authors.initials: Y
authors.lastname: Ma
authors.forename: Shuying
authors.initials: S
authors.lastname: Xiao
authors.forename: Liping
authors.initials: L
authors.lastname: Ding
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.forename: Zhong
authors.initials: Z
authors.lastname: Huang
mesh_terms: D000818:Animals; D001169:Arthritis, Experimental / Q000276:immunology; D001172:Arthritis, Rheumatoid / Q000276:immunology*; D015153:Blotting, Western; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D007150:Immunohistochemistry; D016753:Interleukin-10 / Q000276:immunology*; D020381:Interleukin-17 / Q000276:immunology*; D008264:Macrophages / Q000276:immunology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D057132:Nuclear Receptor Subfamily 1, Group F, Member 3 / Q000276:immunology*; D060888:Real-Time Polymerase Chain Reaction; D015398:Signal Transduction / Q000276:immunology
chemical_list: C556062:IL10 protein, mouse; C098680:Il17a protein, mouse; D020381:Interleukin-17; D057132:Nuclear Receptor Subfamily 1, Group F, Member 3; D016753:Interleukin-10
references.citation: Eur J Immunol. 2000 Jun;30(6):1568-75
references.pmid: 10898492
references.citation: Immunol Rev. 2008 Dec;226:205-18
references.pmid: 19161426
references.citation: Nat Rev Immunol. 2007 Jun;7(6):429-42
references.pmid: 17525752
references.citation: Pharmacol Ther. 2008 Feb;117(2):244-79
references.pmid: 18155297
references.citation: Eur J Immunol. 2008 Jul;38(7):1807-13
references.pmid: 18506885
references.citation: Trends Immunol. 2004 Dec;25(12):677-86
references.pmid: 15530839
references.citation: Cell Mol Immunol. 2013 Nov;10(6):471-82
references.pmid: 24013843
references.citation: Haematologica. 1995 Mar-Apr;80(2):161-75
references.pmid: 7628754
references.citation: Infect Immun. 2003 Jun;71(6):3563-71
references.pmid: 12761141
references.citation: J Clin Invest. 2012 Mar;122(3):787-95
references.pmid: 22378047
references.citation: Arthritis Res Ther. 2011;13(6):R212
references.pmid: 22192790
references.citation: Gastroenterology. 2010 Jun;138(7):2399-409, 2409.e1
references.pmid: 20178793
references.citation: Nat Rev Immunol. 2010 Mar;10(3):170-81
references.pmid: 20154735
references.citation: N Engl J Med. 2009 Aug 27;361(9):888-98
references.pmid: 19710487
references.citation: Nat Med. 2005 Oct;11(10):1066-72
references.pmid: 16170321
references.citation: Proc Natl Acad Sci U S A. 2010 Aug 17;107(33):14751-6
references.pmid: 20679229
references.citation: Nature. 2003 May 15;423(6937):356-61
references.pmid: 12748655
references.citation: J Transl Med. 2011 Dec 16;9:217
references.pmid: 22176654
references.citation: Arthritis Rheum. 2009 May;60(5):1210-21
references.pmid: 19404968
references.citation: Arthritis Res Ther. 2003;5(1):R18-24
references.pmid: 12716449
references.citation: Nat Protoc. 2008;3(4):612-8
references.pmid: 18388943
references.citation: Curr Rheumatol Rep. 2009 Oct;11(5):365-70
references.pmid: 19772832
references.citation: Arthritis Res. 2000;2(3):189-202
references.pmid: 11094428
references.citation: Arthritis Res Ther. 2007;9(6):224
references.pmid: 18177511
references.citation: Nat Rev Immunol. 2008 Dec;8(12):958-69
references.pmid: 19029990
references.citation: J Immunol. 2006 Dec 1;177(11):7551-8
references.pmid: 17114424
references.citation: J Exp Med. 2003 Dec 15;198(12):1951-7
references.pmid: 14662908
references.citation: Inflamm Res. 2002 Feb;51(2):102-4
references.pmid: 11930902
references.citation: Arthritis Rheum. 2004 Feb;50(2):650-9
references.pmid: 14872510
references.citation: Arthritis Res Ther. 2012 Feb 08;14(1):R32
references.pmid: 22315945
references.citation: Eur J Immunol. 2006 Dec;36(12):3248-55
references.pmid: 17111348
references.citation: Arthritis Rheum. 2012 Nov;64(11):3564-73
references.pmid: 22833425
references.citation: Arthritis Res. 2001;3(3):168-77
references.pmid: 11299057
references.citation: J Immunol. 2007 Jun 1;178(11):6705-9
references.pmid: 17513714
references.citation: Mol Cell Biol. 2006 Aug;26(15):5715-27
references.pmid: 16847325
references.citation: Int J Clin Exp Med. 2013;6(2):98-104
references.pmid: 23386912
references.citation: Proc Natl Acad Sci U S A. 2008 Sep 30;105(39):14993-8
references.pmid: 18820032
references.citation: J Biol Chem. 2007 Mar 9;282(10):6965-75
references.pmid: 17194701
references.citation: J Immunol. 2001 Sep 15;167(6):3505-12
references.pmid: 11544344
references.citation: J Immunol. 2007 Apr 15;178(8):4779-85
references.pmid: 17404258
references.citation: Immunology. 1995 Apr;84(4):536-42
references.pmid: 7790026
references.citation: Immunobiology. 2010 Sep-Oct;215(9-10):796-803
references.pmid: 20692534
references.citation: Annu Rev Immunol. 2005;23:901-44
references.pmid: 15771589
references.citation: Arthritis Res Ther. 2011;13(5):R150
references.pmid: 21933391
references.citation: Biotechnol Bioeng. 2014 Jun;111(6):1210-21
references.pmid: 24375008
references.citation: J Exp Med. 1981 Sep 1;154(3):713-25
references.pmid: 7276827
references.citation: J Exp Med. 2005 May 16;201(10):1615-25
references.pmid: 15883173
references.citation: Eur J Immunol. 1981 Oct;11(10):805-15
references.pmid: 7308288
references.citation: J Exp Med. 2003 Jun 2;197(11):1573-83
references.pmid: 12782719
references.citation: Cell. 2006 Sep 22;126(6):1121-33
references.pmid: 16990136