This article has been updated


The spondyloarthropathies are a group of rheumatic diseases that are associated with inflammation at anatomically distal sites, particularly the tendon-bone attachments (entheses) and the aortic root. Serum concentrations of interleukin-23 (IL-23) are elevated and polymorphisms in the IL-23 receptor are associated with ankyosing spondylitis, however, it remains unclear whether IL-23 acts locally at the enthesis or distally on circulating cell populations. We show here that IL-23 is essential in enthesitis and acts on previously unidentified IL-23 receptor (IL-23R)+, RAR-related orphan receptor γt (ROR-γt)+CD3+CD4CD8, stem cell antigen 1 (Sca1)+ entheseal resident T cells. These cells allow entheses to respond to IL-23 in vitro—in the absence of further cellular recruitment—and to elaborate inflammatory mediators including IL-6, IL-17, IL-22 and chemokine (C-X-C motif) ligand 1 (CXCL1). Notably, the in vivo expression of IL-23 is sufficient to phenocopy the human disease, with the specific and characteristic development of enthesitis and entheseal new bone formation in the initial complete absence of synovitis. As in the human condition, inflammation also develops in vivo at the aortic root and valve, which are structurally similar to entheses. The presence of these entheseal resident cells and their production of IL-22, which activates signal transducer and activator of transcription 3 (STAT3)-dependent osteoblast-mediated bone remodeling, explains why dysregulation of IL-23 results in inflammation at this precise anatomical site.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Change history

  • 20 August 2012

    In the version of this article initially published online, the x axis in Figure 6c was incorrectly labeled. The error has been corrected for the print, PDF and HTML versions of this article.


  1. 1.

    , & Are current available therapies disease-modifying in spondyloarthritis? Best Pract. Res. Clin. Rheumatol. 24, 625–635 (2010).

  2. 2.

    Disease modification in ankylosing spondylitis. Nat. Rev. Rheumatol. 6, 75–81 (2010).

  3. 3.

    et al. Adalimumab significantly reduces both spinal and sacroiliac joint inflammation in patients with ankylosing spondylitis: a multicenter, randomized, double-blind, placebo-controlled study. Arthritis Rheum. 56, 4005–4014 (2007).

  4. 4.

    et al. Assessment of radiographic progression in the spines of patients with ankylosing spondylitis treated with adalimumab for up to 2 years. Arthritis Res. Ther. 11, R127 (2009).

  5. 5.

    , & Classification of inflammatory arthritis by enthesitis. Lancet 352, 1137–1140 (1998).

  6. 6.

    et al. Transgenic mice expressing human tumour necrosis factor: a predictive genetic model of arthritis. EMBO J. 10, 4025–4031 (1991).

  7. 7.

    et al. Association of interleukin 23 receptor variants with psoriatic arthritis. J. Rheumatol. 36, 137–140 (2009).

  8. 8.

    et al. Association scan of 14,500 nonsynonymous SNPs in four diseases identifies autoimmunity variants. Nat. Genet. 39, 1329–1337 (2007).

  9. 9.

    et al. A genome-wide association study identifies IL23R as an inflammatory bowel disease gene. Science 314, 1461–1463 (2006).

  10. 10.

    et al. Constitutive p40 promoter activation and IL-23 production in the terminal ileum mediated by dendritic cells. J. Clin. Invest. 112, 693–706 (2003).

  11. 11.

    et al. The evolution of spondyloarthropathies in relation to gut histology. III. Relation between gut and joint. J. Rheumatol. 22, 2279–2284 (1995).

  12. 12.

    , , & From HLA-B27 to spondyloarthritis: a journey through the ER. Immunol. Rev. 233, 181–202 (2010).

  13. 13.

    et al. Endoplasmic reticulum stress-induced transcription factor, CHOP, is crucial for dendritic cell IL-23 expression. Proc. Natl. Acad. Sci. USA 107, 17698–17703 (2010).

  14. 14.

    et al. Increased serum IL-17 and IL-23 in the patient with ankylosing spondylitis. Clin. Rheumatol. 30, 269–273 (2011).

  15. 15.

    et al. Overexpression of interleukin-23, but not interleukin-17, as an immunologic signature of subclinical intestinal inflammation in ankylosing spondylitis. Arthritis Rheum. 60, 955–965 (2009).

  16. 16.

    , , , & Expression of IL-23 and IL-17 and effect of IL-23 on IL-17 production in ankylosing spondylitis. Rheumatol. Int. 29, 1343–1347 (2009).

  17. 17.

    et al. Systemic levels of IL-23 are strongly associated with disease activity in rheumatoid arthritis but not spondyloarthritis. Ann. Rheum. Dis. 69, 618–623 (2010).

  18. 18.

    & Innate IL-17–producing cells: the sentinels of the immune system. Nat. Rev. Immunol. 10, 479–489 (2010).

  19. 19.

    et al. Immunohistologic analysis of zygapophyseal joints in patients with ankylosing spondylitis. Arthritis Rheum. 54, 2845–2851 (2006).

  20. 20.

    et al. Correlation of histopathological findings and magnetic resonance imaging in the spine of patients with ankylosing spondylitis. Arthritis Res. Ther. 8, R143 (2006).

  21. 21.

    et al. Synovial histopathology of psoriatic arthritis, both oligo- and polyarticular, resembles spondyloarthropathy more than it does rheumatoid arthritis. Arthritis Res. Ther. 7, R569–R580 (2005).

  22. 22.

    et al. Histological assessment of the early enthesitis lesion in spondyloarthropathy. Ann. Rheum. Dis. 61, 534–537 (2002).

  23. 23.

    et al. Quantitative analyses of sacroiliac biopsies in spondyloarthropathies: T cells and macrophages predominate in early and active sacroiliitis- cellularity correlates with the degree of enhancement detected by magnetic resonance imaging. Ann. Rheum. Dis. 59, 135–140 (2000).

  24. 24.

    , , , & Identification of types II. IX and X collagens at the insertion site of the bovine achilles tendon. Matrix Biol. 17, 65–73 (1998).

  25. 25.

    , , & An immunohistochemical study of enthesis development in the medial collateral ligament of the rat knee joint. Anat. Embryol. (Berl.) 194, 399–406 (1996).

  26. 26.

    , , & Identification and immunolocalization of type X collagen at the ligament-bone interface. Biochem. Biophys. Res. Commun. 222, 584–589 (1996).

  27. 27.

    , , & Biochemical analysis of collagens at the ligament-bone interface reveals presence of cartilage-specific collagens. Arch. Biochem. Biophys. 328, 135–142 (1996).

  28. 28.

    , , , & Immunohistochemical distribution of type I, II and III collagens in the rabbit supraspinatus tendon insertion. J. Anat. 185, 279–284 (1994).

  29. 29.

    & The joint capsule: structure, composition, ageing and disease. J. Anat. 184, 503–509 (1994).

  30. 30.

    , & Development and ageing of phenotypically distinct fibrocartilages associated with the rat Achilles tendon. Anat. Embryol. (Berl.) 186, 611–618 (1992).

  31. 31.

    , & Development of functionally distinct fibrocartilages at two sites in the quadriceps tendon of the rat: the suprapatella and the attachment to the patella. Anat. Embryol. (Berl.) 185, 181–187 (1992).

  32. 32.

    , , , & Characterization of collagens and proteoglycans at the insertion of the human Achilles tendon. Matrix Biol. 16, 457–470 (1998).

  33. 33.

    et al. Studies on type II collagen induced arthritis in rats: an experimental model of peripheral and axial ossifying enthesopathy. J. Rheumatol. 16, 721–728 (1989).

  34. 34.

    et al. Microdamage and altered vascularity at the enthesis-bone interface provides an anatomic explanation for bone involvement in the HLA-B27–associated spondylarthritides and allied disorders. Arthritis Rheum. 56, 224–233 (2007).

  35. 35.

    et al. Ubiquitous transgenic expression of the IL-23 subunit p19 induces multiorgan inflammation, runting, infertility, and premature death. J. Immunol. 166, 7563–7570 (2001).

  36. 36.

    , , & Minicircle DNA vectors devoid of bacterial DNA result in persistent and high-level transgene expression in vivo. Mol. Ther. 8, 495–500 (2003).

  37. 37.

    , , & Aortitis and periaortitis in ankylosing spondylitis. Joint Bone Spine 78, 451–455 (2011).

  38. 38.

    et al. The orphan nuclear receptor RORγt directs the differentiation program of proinflammatory IL-17+ T helper cells. Cell 126, 1121–1133 (2006).

  39. 39.

    & Autoinflammatory conditions: when to suspect? How to treat? Best Pract. Res. Clin. Rheumatol. 24, 401–411 (2010).

  40. 40.

    et al. CD8 αβ T cells are not essential to the pathogenesis of arthritis or colitis in HLA-B27 transgenic rats. J. Immunol. 170, 1099–1105 (2003).

  41. 41.

    et al. Spondylarthritis in HLA-B27/human β2-microglobulin-transgenic rats is not prevented by lack of CD8. Arthritis Rheum. 60, 1977–1984 (2009).

  42. 42.

    et al. Characteristic magnetic resonance imaging entheseal changes of knee synovitis in spondylarthropathy. Arthritis Rheum. 41, 694–700 (1998).

  43. 43.

    et al. Association of interleukin-23 receptor variants with ankylosing spondylitis. Arthritis Rheum. 58, 1020–1025 (2008).

  44. 44.

    & Development of PLZF-expressing innate T cells. Curr. Opin. Immunol. 23, 220–227 (2011).

  45. 45.

    , & The proliferating cells in autoimmune MRL/lpr mice lack L3T4, an antigen on “helper” T cells that is involved in the response to class II major histocompatibility antigens. J. Immunol. 132, 2686–2689 (1984).

  46. 46.

    et al. IL-23 receptor regulates unconventional IL-17-producing T cells that control bacterial infections. J. Immunol. 184, 1710–1720 (2010).

  47. 47.

    , , , & Lung CD4CD8 double-negative T cells are prominent producers of IL-17A and IFN-γ during primary respiratory murine infection with Francisella tularensis live vaccine strain. J. Immunol. 184, 5791–5801 (2010).

  48. 48.

    et al. Expanded double negative T cells in patients with systemic lupus erythematosus produce IL-17 and infiltrate the kidneys. J. Immunol. 181, 8761–8766 (2008).

  49. 49.

    , & Increased proportion of CD3+CD4CD8 double-negative T cells in peripheral blood of children with Behcet's disease. Autoimmun. Rev. 6, 237–240 (2007).

  50. 50.

    , , , & Behcet's-like syndrome associated with idiopathic CD4+ T-lymphocytopenia, opportunistic infections, and a large population of TCRαβ+ CD4 CD8 T cells. Am. J. Med. Sci. 313, 236–238 (1997).

  51. 51.

    et al. T cell receptor Vβ repertoire of double-negative α/β T cells in patients with systemic sclerosis. Arthritis Rheum. 35, 944–948 (1992).

  52. 52.

    et al. Cutting edge: IL-23 receptor gfp reporter mice reveal distinct populations of IL-17-producing cells. J. Immunol. 182, 5904–5908 (2009).

  53. 53.

    et al. In vivo equilibrium of proinflammatory IL-17+ and regulatory IL-10+ Foxp3+ RORγt+ T cells. J. Exp. Med. 205, 1381–1393 (2008).

  54. 54.

    , & Improved production and purification of minicircle DNA vector free of plasmid bacterial sequences and capable of persistent transgene expression in vivo. Hum. Gene Ther. 16, 126–131 (2005).

Download references


We are grateful for the assistance of S. Jungers for flow cytometric sorting. We also thank P. Bowness, H. Gaston, A. van der Merwe and A. Cooke for helpful comments on this study. This research was funded by and conducted within Merck Research Laboratories. We thank Z.-Y. Chen (Departments of Pediatrics and Genetics, Stanford University School of Medicine) for the minicircle vector plasmid.

Author information

Author notes

    • Jonathan P Sherlock
    • , Barbara Joyce-Shaikh
    • , Drake M LaFace
    •  & Daniel J Cua

    These authors contributed equally to this work.


  1. Merck Research Laboratories, Palo Alto, California, USA.

    • Jonathan P Sherlock
    • , Barbara Joyce-Shaikh
    • , Scott P Turner
    • , Cheng-Chi Chao
    • , Manjiri Sathe
    • , Jeff Grein
    • , Daniel M Gorman
    • , Edward P Bowman
    • , Terrill K McClanahan
    • , Jennifer H Yearley
    • , Robert A Kastelein
    • , Robert H Pierce
    • , Drake M LaFace
    •  & Daniel J Cua
  2. University of Oxford, Trinity College, Oxford, UK.

    • Jonathan P Sherlock
  3. University of Birmingham, Birmingham, UK.

    • Jonathan P Sherlock
    •  & Christopher D Buckley
  4. Institut Pasteur, Paris, France.

    • Gérard Eberl


  1. Search for Jonathan P Sherlock in:

  2. Search for Barbara Joyce-Shaikh in:

  3. Search for Scott P Turner in:

  4. Search for Cheng-Chi Chao in:

  5. Search for Manjiri Sathe in:

  6. Search for Jeff Grein in:

  7. Search for Daniel M Gorman in:

  8. Search for Edward P Bowman in:

  9. Search for Terrill K McClanahan in:

  10. Search for Jennifer H Yearley in:

  11. Search for Gérard Eberl in:

  12. Search for Christopher D Buckley in:

  13. Search for Robert A Kastelein in:

  14. Search for Robert H Pierce in:

  15. Search for Drake M LaFace in:

  16. Search for Daniel J Cua in:


J.P.S. identified the role of IL-23 in enthesitis, designed and performed the experiments to investigate IL-23 induction of rheumatic lesions, developed the methodology to isolate, culture and analyze entheseal cells and prepared the manuscript. B.J.-S. identified the role of IL-22 in entheseal disease and designed and performed IL-22 signaling and antibody blocking studies, as well as studies using antibodies against collagen to induce arthritis. S.P.T. directed and performed the multiphoton microscopy and assisted with flow cytometry. C.-C.C., E.P.B. and C.D.B. provided expert advice about murine arthritis models. M.S., J.G. and T.K.M. provided the gene expression data. D.M.G. produced, validated and provided all gene expression minicircle constructs. J.H.Y. and R.H.P. directed histological studies and analyses and developed an enthesitis scoring system. G.E. provided ROR-γt–eGFP reporter mice and discussed key experimental designs. R.A.K. provided expert advice to enable the IL-23 minicircle project. D.M.L. supervised the project and performed the hydrodynamic injections. D.J.C. directed the project, oversaw the experimental design, data analysis and research direction and prepared the manuscript.

Competing interests

J.P.S., B.J.-S., S.P.T., C.-C.C., M.S., J.G., D.G., E.P.B., T.M., J.H.Y., G.E., C.D.B., R.A.K., R.H.P., D.L. and D.J.C. are employees of Merck & Co, Inc.

Corresponding author

Correspondence to Daniel J Cua.

Supplementary information

PDF files

  1. 1.

    Supplementary Text and Figures

    Supplementary Figures 1–5

About this article

Publication history





Further reading