IL33 and rheumatoid arthritis: In particular, the IL-1 superfamily (IL-1β and IL-33) is known as potent mediators in driving aberrant matrix remodelling in human tenocytes linking inflammation and extracellular matrix(ECM) remodelling.21 22 Furthermore, our data revealed that HMGB1 acted on tenocytes in vitro to enhance the production of the chemokines CCL2 and CXCL12 which have been implicated in RA synovitis23 and are produced by OA synovium24 in the presence of proinflammatory cytokines.