Interleukin-17A Inhibition Diminishes Inflammation and New Bone Formation in Experimental Spondyloarthritis

Melissa N. van Tok, Leonie M. van Duivenvoorde, Ina Kramer, Peter Ingold, Sabina Pfister, Lukas Roth, Iris C. Blijdorp, Marleen G.H. van de Sande, Joel D. Taurog, Frank Kolbinger, Dominique L. Baeten

Research output: Contribution to journalArticlepeer-review

58 Scopus citations


Objective: It remains unclear if and how inflammation and new bone formation in spondyloarthritis (SpA) are coupled. We undertook this study to assess the hypothesis that interleukin-17A (IL-17A) is a pivotal driver of both processes. Methods: The effect of tumor necrosis factor (TNF) and IL-17A on osteogenesis was tested in an osteoblastic differentiation assay using SpA fibroblast-like synoviocytes (FLS) differentiated with dexamethasone, β-glycophosphatase, and ascorbic acid. IL-17A blockade was performed in HLA–B27/human β 2 -microglobulin (hβ 2 m)–transgenic rats, which served as a model for SpA in both prophylactic and therapeutic settings. Inflammation and new bone formation were evaluated by micro–computed tomography imaging, histologic analysis, and gene expression profiling. Results: TNF and IL-17A significantly increased in vitro osteoblastic differentiation. In vivo, prophylactic blockade of IL-17A significantly delayed spondylitis and arthritis development and decreased arthritis severity. Anti–IL-17A treatment was also associated with prevention of bone loss and periosteal new bone formation. Therapeutic targeting of IL-17A after the initial inflammatory insult also significantly reduced axial and peripheral joint inflammation. This treatment was again associated with a marked reduction in spinal and peripheral structural damage, including new bone formation. RNA sequencing of target tissue confirmed that IL-17A is a key driver of the molecular signature of disease in this model and that therapeutic anti–IL-17A treatment reversed the inflammatory signature and the selected gene expression related to bone damage. Conclusion: Both prophylactic and therapeutic inhibition of IL-17A diminished inflammation and new bone formation in HLA-B27/hβ 2 m–transgenic rats. Taken together with the ability of IL-17A to promote osteoblastic differentiation of human SpA FLS, these data suggest a direct link between IL-17A–driven inflammation and pathologic new bone formation in SpA.

Original languageEnglish (US)
Pages (from-to)612-625
Number of pages14
JournalArthritis and Rheumatology
Issue number4
StatePublished - Apr 2019

ASJC Scopus subject areas

  • Immunology and Allergy
  • Rheumatology
  • Immunology


Dive into the research topics of 'Interleukin-17A Inhibition Diminishes Inflammation and New Bone Formation in Experimental Spondyloarthritis'. Together they form a unique fingerprint.

Cite this