IL-17 receptor and its functional significance in psoriatic arthritis

Mol Cell Biochem. 2012 Jan;359(1-2):419-29. doi: 10.1007/s11010-011-1036-6. Epub 2011 Sep 6.


To delineate the functional significance of IL-17 Receptor (IL-17RA) and characterize the IL-17 producing T cell (Th17) subpopulation in psoriatic arthritis (PsA). Mononuclear cells from blood and synovial fluid (SF) were obtained from PsA (n=20), rheumatoid arthritis (RA, n=20) and osteoarthritis (OA, n=20) patients. Synoviocytes (FLS) were isolated from the synovium of RA (n=5), PsA (n=5) and OA (n=5) patients. IL-17RA expression in FLS was identified by western blotting (WB) and flowcytometry. T lymphocytes derived from the SF of these patients were studied to identify and phenotype the Th17 cells. The functional significance of IL-17RA was determined by evaluating its regulatory role on the production of proinflammatory cytokines and endopeptidase. IL-17RA expression was found to be significantly higher in FLS of RA (15.7%±4.9) and PsA (4.5%±0.9) in comparison to OA (1.14%±0.9). Western blot analyses showed that the relative intensity (RI) of IL-17RA protein was higher in RA and PsA compared to OA (Fisher exact, P<0.01). A significant enrichment of IL-17-producing CD4+ T cells (7.9%±2.8) was observed in the SF of PsA patients compared to that of OA patients (P<.001). Compared to OA-FLS, recombinant IL-17 induced higher levels of IL-6, IL-8, and MMP-3 production in PsA-FLS. Blockage of IL-17RA with an anti-IL-17RA antibody inhibited the production of IL-6, IL-8, and MMP-3. This is the first report to demonstrate the functional significance of IL-17RA in PsA. Results of this study support the hypothesis that IL-17RA blocking antibodies have the potential to be a therapeutic option for psoriatic arthritis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibodies, Blocking / pharmacology
  • Arthritis, Psoriatic / etiology
  • Arthritis, Psoriatic / immunology*
  • Arthritis, Psoriatic / pathology
  • Arthritis, Rheumatoid / etiology
  • Arthritis, Rheumatoid / immunology
  • Case-Control Studies
  • Humans
  • Interleukin-6
  • Interleukin-8
  • Matrix Metalloproteinase 3
  • Receptors, Interleukin-17 / immunology*
  • Synovial Fluid / immunology
  • Th17 Cells / immunology


  • Antibodies, Blocking
  • Interleukin-6
  • Interleukin-8
  • Receptors, Interleukin-17
  • Matrix Metalloproteinase 3