TNF-α is heavily upregulated in the synovial fluid (SF) of RA patients (Chu et al., 1991), is known to directly impair endothelial function by inciting production of nuclear factor κB (NF-κB) and reactive oxygen species (ROS) (Di Minno et al., 2015), and plays a pivotal role in disease pathogenesis (Ursini et al., 2017). Here, TNF is linked to rheumatoid arthritis.