Th17 Cells, Not IL-17+ δγ T Cells, Drive Arthritic Bone Destruction in Mice and Humans This information is current as Bernadette Pöllinger, Tobias Junt, Barbara Metzler, Ulrich of September 29, 2021. A. Walker, Alan Tyndall, Cyril Allard, Serkan Bay, Roland Keller, Friedrich Raulf, Franco Di Padova, Terrence O'Reilly, Nicole J. Horwood, Dhavalkumar D. Patel and Amanda Littlewood-Evans J Immunol 2011; 186:2602-2612; Prepublished online 7 Downloaded from January 2011; doi: 10.4049/jimmunol.1003370 http://www.jimmunol.org/content/186/4/2602 http://www.jimmunol.org/ Supplementary http://www.jimmunol.org/content/suppl/2011/01/07/jimmunol.100337 Material 0.DC1 References This article cites 53 articles, 20 of which you can access for free at: http://www.jimmunol.org/content/186/4/2602.full#ref-list-1 Why The JI? Submit online. by guest on September 29, 2021 • Rapid Reviews! 30 days* from submission to initial decision • No Triage! Every submission reviewed by practicing scientists • Fast Publication! 4 weeks from acceptance to publication *average Subscription Information about subscribing to The Journal of Immunology is online at: http://jimmunol.org/subscription Permissions Submit copyright permission requests at: http://www.aai.org/About/Publications/JI/copyright.html Email Alerts Receive free email-alerts when new articles cite this article. Sign up at: http://jimmunol.org/alerts The Journal of Immunology is published twice each month by The American Association of Immunologists, Inc., 1451 Rockville Pike, Suite 650, Rockville, MD 20852 Copyright © 2011 by The American Association of Immunologists, Inc. All rights reserved. Print ISSN: 0022-1767 Online ISSN: 1550-6606. The Journal of Immunology Th17 Cells, Not IL-17+ gd T Cells, Drive Arthritic Bone Destruction in Mice and Humans Bernadette Po¨llinger,* Tobias Junt,* Barbara Metzler,* Ulrich A. Walker,† Alan Tyndall,† Cyril Allard,* Serkan Bay,* Roland Keller,* Friedrich Raulf,* Franco Di Padova,* Terrence O’Reilly,‡,1 Nicole J. Horwood,x Dhavalkumar D. Patel,* and Amanda Littlewood-Evans* The mechanism whereby IL-17 drives rheumatoid arthritis remains incompletely understood. We demonstrate that anti–IL-17 therapy in collagen-induced arthritis ameliorates bone damage by reducing the number of osteoclasts in joints. We found equal numbers of CD4+ Th17 and IL-17 producing gd T cells in the joints of arthritic mice, and in vitro, both populations similarly induced osteoclastogenesis. However, individual depletion and adoptive transfer studies revealed that in vivo, Th17 cells domi- Downloaded from nated with regard to bone destruction. Unlike gd T cells, Th17 cells were found in apposition to tartrate-resistant acid phospha- tase positive osteoclasts in subchondral areas of inflamed joints, a pattern reproduced in patient biopsies. This localization was caused by Ag-specific retention, because OVA-primed Th17 cells showed a gd T cell-like diffuse distribution. Because IL-23, as produced by osteoclasts, enhanced T cell-mediated osteoclastogenesis, we propose that Ag-specific juxtaposition is key to foster the molecular cross talk of Th17 cells and osteoclasts, thus driving arthritic bone destruction. The Journal of Immunology, 2011, 186: 2602–2612. http://www.jimmunol.org/ heumatoid arthritis (RA) is a chronic autoimmune disease In collagen-induced arthritis (CIA), disease was markedly sup- characterized by immune cell invasion into the joint space, pressed in IL-17–deficient mice (13). Major sources of IL-17 in R cytokine imbalance, inflammation of the synovial mem- this model are CD4+ T cells (Th17) and IL-17–secreting gd branes, and progressive synovial fibroblast- and osteoclast-mediated T cells. Although both cell types have the potential to exacerbate joint destruction (1). There is mounting evidence that osteoclasts, CIA (14, 15), the relative significance of IL-17+ gd T cells and synoviocytes, and immune cells communicate via cytokines and other Th17 cells in arthritis remains to be shown (16–18). signaling molecules. Factors derived from activated T cells are known A strong link between the proinflammatory activity of IL-23 and to affect the differentiation and activation of pathogenic osteoclasts cells of the Th17 lineage has been established. IL-23 stabilizes the by guest on September 29, 2021 (2, 3). The role of IL-17, a T cell-derived inflammatory cytokine has Th17 lineage, thereby generating large numbers of IL-17–producing been of particular interest recently because it was found that it effector cells (19). Consequently, IL-23–deficient mice are protected exacerbates autoimmune diseases such as RA (4). The relevance of from autoimmune diseases such as CIA (20) and resistance corre- this cytokine in RA is highlighted by the current success of clinical lated with an absence of IL-17–producing CD4+ T cells. In addition, trials with neutralizing Abs to IL-17 (5, 6). This cytokine has been there is evidence that IL-23 affects cells of the innate immune sys- described to orchestrate diverse immune functions such as elicitation tem. For example, IL-23 is required to induce IL-17A production of proinflammatory mediators from joint-resident cells, chemo- from NKT cells, gd T cells, and Thy1+ SCA1+ innate immune cells attraction of neutrophils, stimulation of receptor activator for NF-kB (21–25). The IL-23/IL-17 axis has been described to play a pivotal ligand (RANKL) expression, a factor that is crucial for osteoclasto- role in the autoimmune inflammation in joints. Indeed, in RA, IL- genesis, as well as mediate direct pro-osteoclastogenic effects (7–12). 23p19 levels correlate with those of IL-17 in the synovial fluid and with IL-17, TNF-a, and IL-1b levels in the serum. Furthermore, synovial IL-23p19 levels were found to be greater in patients with *Department of Autoimmunity, Transplantation and Inflammation, Novartis Insti- tutes for BioMedical Research, 4002 Basel, Switzerland; †Department of Rheuma- bone erosions (26). Cross talk between IL-23 and IL-17 is particu- tology, Felix Platter Spital, 4012 Basel, Switzerland; ‡Department of Oncology, larly associated with the destruction phase of RA characterized by x Novartis Institutes for BioMedical Research, 4002 Basel, Switzerland; and Kennedy the T cell-mediated activation of osteoclastogenesis (27). Institute of Rheumatology, Imperial College of Science, Technology and Medicine, London, W6 8LH United Kingdom In this study, we identified the relative pro-osteoclastogenic + 1Retired. contributions of IL-17–secreting gd and CD4 T cells in the CIA Received for publication October 12, 2010. Accepted for publication December 8, model and relate these findings to RA. 2010. Address correspondence and reprint requests to Dr. Amanda Littlewood-Evans, De- partment of Autoimmunity, Transplantation and Inflammation, Novartis Institutes for Materials and Methods BioMedical Research, Forum 1 Novartis Campus, Basel 4002, Switzerland. E-mail Mice address: [email protected] Eight- to 10-wk-old DBA/1 male mice (Janvier) were used in accordance The online version of this article contains supplemental material. with Swiss Federal and Cantonal Authorities. Abbreviations used in this article: CIA, collagen-induced arthritis; IHC, immunohis- tochemistry; qRT-PCR, quantitative real-time PCR; RA, rheumatoid arthritis; Human samples RANKL, receptor activator for NF-kB ligand; ROR, retinoic acid-related orphan receptor; TRAP, tartrate-resistant acid phosphatase. Synovial fluid from three patients (60–68 y old) with RA based on American College of Rheumatology criteria were obtained from the Felix- Copyright Ó 2011 by The American Association of Immunologists, Inc. 0022-1767/11/$16.00 Platter and University Hospital Basel. Duration of RA ranged from 16 to www.jimmunol.org/cgi/doi/10.4049/jimmunol.1003370 The Journal of Immunology 2603 20 y. Patients were undergoing cortisone treatment and one received ionomycin (Sigma-Aldrich). After activation, cells were stained for in- abatacept. Informed consent from patients was obtained, and studies were tracellular cytokines using an intracellular cytokine staining kit (BD Phar- conducted under guidance/agreement from the Basel Ethical Commission. mingen). Abs were purchased from BD Pharmingen or eBioscience. Before Paraffin-embedded RA synovial tissue from a patient with chronic RA (53 staining, Fc-blockade (anti-CD16/32) was performed. For FACS, T cell y) treated with prednisolone, diclofenac, and leflunomide was purchased populations were first gated on CD45 and subsequently on CD3+CD4+ and from Asterand. Activities of Asterand and their collaborators were con- CD3+gdTCR+CD42, respectively. For mouse, we employed the following ducted in accordance with applicable laws, regulations, and ordinances. Abs: FITC-IFN-g, PE–IL-17, FITC- or PerCP-CD45, allophycocyanin-CD3, Human metacarpal joints were obtained by informed consent from five RA biotinylated gdTCR, Alexa 488- or PerCP-CD4, PE-CD3, CD11b-PerCP, patients (four women and one man) undergoing joint replacement surgery FITC–Ki-67, allophycocyanin-Gr1, streptavidin-PerCP, and streptavidin- under the terms of the ethical approval granted by the combined office of allophycocyanin. For human, we used the following Abs: FITC-IFN-g, PE- research ethics committee (COREC No. 07/Q0411/30). Patients were aged gdTCR, PE-CD4, PerCP-CD3, and AlexaFluor647-IL-17A. Flow cytometry 44–65 y of age at the time of surgery. data were acquired on a FACSCalibur (BD Bioscience) and analyzed with FlowJo 6.42 software (Tree Star). Cell sorting was performed on a FACSAria CIA