TNF and inflammatory bowel disease: Although the exact pathogenesis of IBD is not clear, it is generally accepted that the uncontrolled immune responses lead to intestinal inflammation, which is associated with the increase of pro-inflammatory cytokines including tumor necrosis factor-α (TNF-α) and interleukins such as Interleukin-1β (IL-1β), Interleukin-6 (IL-6), and Interleukin-8 (IL-8) in the intestine (3, 4).