TLR4 and inflammatory bowel disease: The TLR4/MD-2 complex at the cell surface and endosomes is the receptor of LPS, which can be activated by LPS and trigger the downstream immune responses, such as inducing MAP kinases and NF-κB and activating p38 and JNK.149,150 LPS-induced host inflammation is associated with various diseases, such as IBD inflammatory bowel diseases (IBD), obesity, insulin resistance, and autoimmune and allergic diseases.151–153