Moreover, synovial T-cells and macrophages in patients with RA were demonstrated to have significantly higher levels of PD-1/PD-L1 expression than those in healthy controls, with proinflammatory cytokines such as IFN-γ and TNF-α contributing to the upregulation of these costimulatory molecules to some extent (174). The gene discussed is TNF; the disease is rheumatoid arthritis.