Resolution of synovitis and arrest of catabolic and anabolic bone changes in patients with psoriatic arthritis by IL-17A blockade with secukinumab: results from the prospective PSARTROS study.
Collectively, our data suggest that activation of a CD31-driven, αβTCR-independent, IL-17A-mediated T cell-FLC inflammatory circuit drives and/or perpetuates synovitis.
Similar observations apply for rheumatoid arthritis (RA) where IL-17A triggers changes in the synovium that lead to synovitis and maintain local inflammation.
However, mast cells expressed significantly more interleukin-17 (IL-17) in SpA than in RA synovitis, and mast cells constituted the major IL-17-expressing cell population in the SpA synovium.
Pannus and synovitis fibroblasts explanted from tissue samples were cultured in vitro without and with TNF-alpha, IL-1Beta or IL-17 and analyzed quantitatively for RANKL expression.