However, when the integrity of the barrier is damaged, by either pathogenic microorganisms or by host factors, a cascade of events is triggered by exogenous endotoxins or lipopolysaccharides (LPS) or by endogenous tumor necrosis factor (TNF) and interleukin-1 (IL-1) being two master cytokine switches in IBD (16). Here, TNF is linked to inflammatory bowel disease.