众所周知,我们的肠道内部寄生着大量的微生物群,这些微生物中有相当一部分对人体是有益的。比如细菌分泌的维生素以及短链脂肪酸能够促进肠道免疫系统的发育。同时,宿主也进化出一些手段来避免不正常的肠道炎症反应。比如肠道上皮覆盖的粘膜层以及抗菌肽能够有效阻止微生物与宿主细胞的过分接触。 It is well known that a large number of microorganisms are parasitic in our intestine and that a considerable proportion of these microorganisms are beneficial to the human body. Such as bacteria, vitamins and short-chain fatty acids can promote the development of the intestinal immune system. At the same time, the host has evolved some means to avoid abnormal intestinal inflammation. For example, intestinal epithelial mucosa covered layer and antimicrobial peptides can effectively prevent microorganisms and host cells over-contact.