The levels of IL-17, IL-10, and IL-1β were significantly lower (paired t-test, p = 0.026, p = 0.034, and p < 0.001, respectively) and the levels of IL-4 were significantly higher in Exo-RA-treated wells than in untreated cells (paired t-test, p = 0.034; Fig. 3). This evidence concerns the gene IL4 and rheumatoid arthritis.