TNF and irritable bowel syndrome: Organ culture of inflamed mucosal samples from patients with active IBD (CD and UC), have confirmed that co-culture with non-pathogenic Escherichia coli strains strongly stimulates release of proinflammatory cytokines (IL-6, IL-23p19, IL-12p35, IL-17F, IFN-γ, TNF-α), proinflammatory chemokines (IL-8, CXCL-1 and CXCL-2), which activates the inflammatory cascade, whereas the level of TNF-α and IL-6 was significantly lower in healthy controls or when non-pathogenic E coli strains were co-cultured with Lactobacillus casei [197, 198].