Cytokines are secreted proteins released by cells that have specific effects for cellular interactions and communications. Inflammatory cytokines including transforming growth factor-β (TGF-β), tumor necrosis factor-α (TNF-α), platelet-derived growth factor (PDGF), and the interleukins, (IL)-1 and IL-8 have been implicated in the pathogenesis of various autoimmune diseases, such as rheumatoid arthritis (RA), inflammatory bowel diseases (IBD), and lung fibrosis. TNF-α is among the "master regulators" of the inflammatory (immune) responses in many organ systems. The introduction of TNF-α blocking therapy in 1998 began a new era in the treatment of chronic inflammatory human diseases, including RA, ankylosing spondylitis (AS), plaque psoriasis, psoriatic arthritis (PsA), IBD, and ulcerative colitis. Anti-TNF-α antibodies are currently being used clinically with high demand. However, therapeutic antibodies are expensive and require frequent injection. Thus, to develop TNF-α vaccine has its strengths toward clinical application. In this project, we are aiming to develop TNF-α DNA vaccine against inflammatory diseases, which will minimize the frequent injection of therapeutic antibodies.