IBD was not developed or progressed in germ-free IL-10-deficient or IL-2 receptor-deficient animals as well as in TLR-4 knockout animals, by colitic inducers, dextran sulfate sodium (DSS) and 2,4,6-trinitrobenzene sulfonic acid (TNBS) [9-11]. Here, TLR4 is linked to inflammatory bowel disease.