Previous animal experiments have confirmed that TRAILPEG ameliorates arthritis severity and significantly reduces the accumulation of inflammatory molecules (p-p65, ICAM-1, Cox-2, MMP3 and iNOS), pro-inflammatory cytokines (TNF-α, IL-1β, IFN-γ, IL-6, IL-17) and activated macrophages (58), all of which have been shown to play a cellular and cellular component in important role in the pathogenesis of RA. This evidence concerns the gene TNF and rheumatoid arthritis.