TNF and colitis: Acute DSS-induced colitis is characterized by an increase in pro-inflammatory cytokines TNF-α and IFN-γ which are the major proinflammatory cytokines that synergistically drive epithelial barrier dysfunction and apoptosis, particularly during colitis, while chronic DSS-induced colitis comprises focal Wnt/β-catenin mediated epithelial regeneration and both Th1 and Th2 cytokine profiles32–34.