JAK3, STAT4, and STAT6 are also highly expressed in CD1a+ dendritic cells of patients with RA and may help to identify RA at the synovium level.184–188 Mouse models of proteoglycan-induced arthritis revealed that IL-4 controls inflammatory responses in RA by inhibiting IL-12-STAT4 signaling. This evidence concerns the gene STAT4 and Arthritis.