The role of synovial fluid cytokines IL-6, IL-23 and IL-17 in the pathogenesis and persistence of synovial inflammation in JIA patients

Objective Recent data in adult Rheumatoid Arthritis support that the Th17 cell-derived cytokine interleukin 17 (IL-17) in the presence of IL-6 and IL-23 plays a critical role in the pathogenesis of chronic destructive arthritis. Data on synovial fluid (SF) concentrations of IL-17 in JIA pts are sparse. We measured concentrations of the above 3 cytokines and assessed the CD4+CD25highFoxP3+ (Treg) and CD4+CD25lowFoxP3T cell subpopulations in the SF of children with JIA. Findings were correlated with SF sRANKL which expresses the osteoclastic activity in active disease.