In certain autoimmune diseases, such as rheumatoid arthritis (RA), autoimmune thyroid disease, Graves’ ophthalmopathy (GO), and autoimmune diabetes, studies have shown that excessive expression of CD80 and CD86 may lead to overactivation of T cells and enhanced inflammatory responses, thereby promoting the development of autoimmune pathologies (7–11). Here, CD86 is linked to rheumatoid arthritis.