Neish Andrew S
1 Department of Pathology, Emory University School of Medicine, Atlanta, Georgia.
Ann Am Thorac Soc. 2014 Jan;11 Suppl 1(Suppl 1):S28-32. doi: 10.1513/AnnalsATS.201306-161MG.
By definition, the mucosal immune system is responsible for interfacing with the outside world, specifically responding to external threats, of which pathogenic microbes represent a primary challenge. However, it has become apparent that the human host possesses a numerically vast and taxonomically diverse resident microbiota, predominantly in the gut, and also in the airway, genitourinary tract, and skin. The microbiota is generally considered symbiotic, and has been implicated in the regulation of cellular growth, restitution after injury, maintenance of barrier function, and importantly, in the induction, development, and modulation of immune responses. The mucosal immune system uses diverse mechanisms that protect the host from overt pathogens, but necessarily has coevolved to monitor, nurture, and exploit the normal microbiota. As a whole, mucosal immunity encompasses adaptive immune regulation that can involve systemic processes, local tissue-based innate and inflammatory events, intrinsic defenses, and highly conserved cell autonomous cytoprotective responses. Interestingly, specific taxa within the normal microbiota have been implicated in roles shaping specific adaptive, innate, and cell autonomous responses. Taken together, the normal microbiota exerts profound effects on the mucosal immune system, and likely plays key roles in human physiology and disease.
根据定义，黏膜免疫系统负责与外界接触，特别是对外部威胁作出反应，其中病原微生物是主要挑战。然而，显而易见的是，人类宿主拥有数量庞大且分类学上多样的常驻微生物群，主要存在于肠道，也存在于气道、泌尿生殖道和皮肤。微生物群通常被认为是共生的，并且与细胞生长的调节、损伤后的修复、屏障功能的维持有关，重要的是，还与免疫反应的诱导、发育和调节有关。黏膜免疫系统利用多种机制保护宿主免受明显的病原体侵害，但必然已经共同进化以监测、培育和利用正常微生物群。总体而言，黏膜免疫包括适应性免疫调节，这可能涉及全身过程、基于局部组织的固有和炎症事件、内在防御以及高度保守的细胞自主细胞保护反应。有趣的是，正常微生物群中的特定分类群已被认为在塑造特定的适应性、固有性和细胞自主反应中发挥作用。综上所述，正常微生物群对黏膜免疫系统产生深远影响，并可能在人类生理和疾病中起关键作用。
