Moreover, no significant differences were observed in STAT3 and STAT5 expression in peripheral blood-derived CD4pos cells in RA patients treated with CTLA4-Ig based on the fulfillment of the cut-off values of IL6 plasma levels and CD4posCD25posFoxP3pos cell rates associated with DAS remission achievement at 6 months FU (Supplementary Fig. 3). Here, IL6 is linked to rheumatoid arthritis.