Vogt Stefanie L, Finlay B Brett
Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada.
Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada.
J Travel Med. 2017 Apr 1;24(suppl_1):S39-S43. doi: 10.1093/jtm/taw086.
The mammalian gut microbiota is a highly abundant and diverse microbial community that resides in the gastrointestinal tract. One major benefit that the gut microbiota provides to its host is colonization resistance-the ability to prevent colonization by foreign microbes, including diarrheal pathogens such as Clostridium difficile , Salmonella enterica serovar Typhimurium and diarrheagenic Escherichia coli .
We conducted a literature review of the effects of the gut microbiota on infection by diarrheal pathogens. We used PubMed to search for relevant articles published before July 2016, as well as incorporated data from our laboratory.
The gut microbiota provides protection from diarrheal infections both by direct inhibition of pathogens and by indirect effects on host functions. Direct effects of the microbiota on diarrheal pathogens include competing for nutrients and producing metabolites that inhibit pathogen growth or virulence. Indirect effects of the gut microbiota include promoting maintenance of the gut mucosal barrier and stimulating innate and adaptive immunity.
Human epidemiological studies and experimental infections of laboratory animals both demonstrate that antibiotic treatment can alter the gut microbial community and thereby reduce colonization resistance against diarrheal pathogens. Further research might lead to the development of next-generation probiotics that could be used to bolster colonization resistance and thus prevent travellers' diarrheal.
哺乳动物肠道微生物群是栖息于胃肠道的高度丰富且多样的微生物群落。肠道微生物群为其宿主提供的一个主要益处是定殖抗性——防止外来微生物定殖的能力，这些外来微生物包括腹泻病原体，如艰难梭菌、鼠伤寒沙门氏菌和致泻性大肠杆菌。
我们对肠道微生物群对腹泻病原体感染的影响进行了文献综述。我们使用PubMed搜索2016年7月之前发表的相关文章，并纳入了我们实验室的数据。
肠道微生物群通过直接抑制病原体以及对宿主功能的间接影响来提供对腹泻感染的保护。微生物群对腹泻病原体的直接影响包括竞争营养物质和产生抑制病原体生长或毒力的代谢产物。肠道微生物群的间接影响包括促进肠道黏膜屏障的维持以及刺激先天免疫和适应性免疫。
人类流行病学研究和实验动物的实验性感染均表明，抗生素治疗可改变肠道微生物群落，从而降低对腹泻病原体的定殖抗性。进一步的研究可能会导致开发下一代益生菌，可用于增强定殖抗性，从而预防旅行者腹泻。
