IL6 and rheumatoid arthritis: In IMRDs, NR4A subfamily members are aberrantly expressed in inflamed RA and PsA synovium, Ps dermal tissue, SSc fibrotic tissue and OA cartilage compared with normal tissue (53–57) NR4A1-3 receptor levels are induced by, and subsequently modulate cellular responses to key mediators in IMRD and OA, including TNF, IL-6, IL-1β, prostaglandins, growth factors and adenosine (58–60).