Duchmann R, Neurath M, Märker-Hermann E, Meyer Zum Büschenfelde K H
I. Medical Clinic, University of Mainz.
Z Gastroenterol. 1997 May;35(5):337-46.
The intestinal mucosa constitutes an important barrier as it separates each individual from a large array of antigens within the bowel lumen. These luminal antigens may either be derived from pathogens or may be derived from harmless constituents such as ingested food or the normal intestinal flora. The dichotomy of potentially harmful and potentially harmless antigens encountered by the mucosal immune system poses the important task that, with regard to bacteria-derived antigens, the gut associated immune system is required to mount an efficient host defense against pathogenic bacteria but to maintain at the same time the regulatory control mechanisms which protect the human organism from hyperresponsiveness, and thus chronic inflammation, towards antigens from the normal intestinal flora. In the present review, we discuss variable host and bacterial factors which are likely to determine whether the immune response to pathogenic or normal intestinal bacteria will have beneficial or detrimental consequences for the human organism. Using infections with the prototype enteropathogens V. cholerae and enteropathogenic E. coli (ETEC), Y. enterocolitica induced reactive arthritis (ReA) and in more detail, inflammatory bowel diseases (IBD) as exemplary clinical situations, we review current hypotheses of how bacteria or their products are encountered by cellular components of the specific immune system and how this may relate to disease pathogenesis and the development of new treatment strategies.
肠黏膜构成了一道重要的屏障，因为它将个体与肠腔内大量的抗原分隔开来。这些腔内抗原可能源自病原体，也可能源自无害成分，如摄入的食物或正常肠道菌群。黏膜免疫系统所遇到的潜在有害和潜在无害抗原的二分法带来了一项重要任务，即对于细菌衍生的抗原，肠道相关免疫系统既要对病原菌发起有效的宿主防御，又要同时维持调节控制机制，以保护人体免受对正常肠道菌群抗原的过度反应，进而避免慢性炎症。在本综述中，我们讨论了各种宿主和细菌因素，这些因素可能决定对致病性或正常肠道细菌的免疫反应对人体是产生有益还是有害的后果。以感染典型肠道病原体霍乱弧菌、肠致病性大肠杆菌（ETEC）、小肠结肠炎耶尔森菌诱发的反应性关节炎（ReA），以及更详细地以炎症性肠病（IBD）作为示例性临床情况为例，我们回顾了当前关于特定免疫系统的细胞成分如何接触细菌或其产物，以及这如何与疾病发病机制和新治疗策略的发展相关的假说。
