CD4 and rheumatoid arthritis: Notably, in untreated rheumatoid arthritis (RA) patients, the expression of ARID5a in CD4+ T cells is enhanced, whereas treatment with the anti-IL6R antibody tocilizumab results in a decrease in the expression of Arid5a [204], indicating that the IL-6-ARID5A axis may be involved in the pathogenesis of RA.