Wagner Robert Doug
National Center for Toxicological Research, Microbiology Division, Jefferson, Arkansas 72079, USA.
Adv Exp Med Biol. 2008;635:41-56. doi: 10.1007/978-0-387-09550-9_4.
The complex interactions between the GI tract microbiota and the immune system can be simplified for study using gnotobiotic animal models. The importance of cytokines, such as IFN-gamma, TNF-alpha, TGF-beta, Interleukin-2, IL-4 and IL-10 in the host response to intestinal bacteria has been evaluated using gnotobiotic studies. Gnotobiotic experiments with immunodeficient animals have revealed insights into the relationships between innate, cell-mediated and antibody-mediated immune system components in resistance to infectious microorganisms. The development and maturation of the immune system is dependent on the presence of some members of the intestinal microbiota. The commensal microorganisms, in turn, are dependent on the environment and nutrients provided by the GI tract of the host. Gnotobiotic studies are starting to reveal how the microbiota influences oral tolerance to dietary and commensal bacterial antigens. The immunomodulatory effects of microbiota and probiotics for inflammatory bowel diseases and the role of bacteria in their etiologies are being studied in gnotobiotic systems. Many aspects of the host interaction with the microbiota have been and will continue to be best addressed in gnotobiotic experimental models. This chapter reviews the contributions that gnotobiology has made to our understanding of the microbiota and host GI tract health.
使用悉生动物模型可以简化胃肠道微生物群与免疫系统之间复杂的相互作用，以便进行研究。利用悉生研究评估了细胞因子，如干扰素-γ、肿瘤坏死因子-α、转化生长因子-β、白细胞介素-2、白细胞介素-4和白细胞介素-10在宿主对肠道细菌反应中的重要性。对免疫缺陷动物进行的悉生实验揭示了先天性、细胞介导和抗体介导的免疫系统成分在抵抗传染性微生物方面的关系。免疫系统的发育和成熟依赖于肠道微生物群的某些成员的存在。反过来，共生微生物依赖于宿主胃肠道提供的环境和营养。悉生研究开始揭示微生物群如何影响对饮食和共生细菌抗原的口服耐受性。在悉生系统中正在研究微生物群和益生菌对炎症性肠病的免疫调节作用以及细菌在其病因中的作用。宿主与微生物群相互作用的许多方面已经并将继续在悉生实验模型中得到最好的解决。本章综述了悉生生物学对我们理解微生物群和宿主胃肠道健康所做的贡献。
