IL17A and rheumatoid arthritis: The results showed that the number of lymphocyte subsets including total T, total B, NK, CD4+ T, and CD8+ T cells and CD4+ T-cell subsets including Th1, Th2, Th17, and Treg cells in D2T RA patients was lower than that in the new, treated RA, and healthy control groups, while the IL-6, IL-17, and TNF-α cytokines were significantly higher than those in the healthy control group.