IL6 and rheumatoid arthritis: All of the cytokines assayed were significantly elevated in the sera of RA patients compared to healthy controls with the dominance of IL-6 and IL-17A over the others: IL-6 (q = 0.001); IL-17A (q = 0.001); TNF-α (q = 0.017); IL-23 (q = 0.03).