CD4 and rheumatoid arthritis: Accordingly, an analysis of peripheral blood CD4+ and CD8+ T cells from patients with rheumatoid arthritis, placed in culture and stimulated with PMA and ionomycin or with αCD3αCD28 in the presence of brefeldin A, verified the expression of Th1 and Th2 profile cytokines IL-2, IFN-γ, IL-4, IL-5, IL-13, and IL-10 in these cells and concluded that the percentages of expression of these cytokines were very similar in patients with rheumatoid arthritis compared to controls without any type of autoimmune disease [49].