The pathophysiology of the RA is not completely understood yet (Imboden, 2009), But previous studies have confirmed that pro‐inflammatory cytokines, such as TNF‐α, IL‐1 and IL‐6, mainly produced by increased numbers of macrophages, are responsible for the inflammation and joint destruction (Guo et al., 2018). Here, TNF is linked to rheumatoid arthritis.