TLRs such as TLR2, TLR4 and TLR9 are thought to be the major receptors for recognizing bacteria and have been found to be up-regulated in AP.6 Moreover, TLR4 mediates the recognition of bacterial lipopolysaccharides (LPS) and is thought to be highly correlated with system inflammatory reaction syndrome (SIRS), hence TLR4 has been widely studied as a potential mechanistic target for the treatment of AP.6 However, TLR4-related researches in AP were controversial and the methods using for previous studies all focused on systemic rather than local knockout of this receptor.7,8. This evidence concerns the gene TLR4 and systemic inflammatory response syndrome.