基因与微生物群的相互作用有助于炎症性肠病的发生
Hiutung Chu1, Arya Khosravi2, Indah P Kusumawardhani2
1Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA. hiuchu@caltech.edu sarkis@caltech.edu.
概括
炎症性肠病 (IBD) 的遗传风险变异会损害免疫系统感知有益肠道细菌信号的能力. 这种缺陷阻碍了调节性T细胞 (Tregs) 的激活,导致IBD的发展.
科学领域:
- 微生物学
- 免疫学
- 遗传学
背景情况:
- 炎症性肠病 (IBD) 与遗传风险变异和肠道微生物组失调有关.
- 缺乏将这些因素与IBD病原体联系起来的统一原则.
- 像Bacteroides fragilis这样的共生细菌通过外膜囊泡 (OMV) 与宿主免疫细胞进行通信.
研究的目的:
- 研究IBD相关基因ATG16L1和NOD2在宿主对微生物OMV的反应中的作用.
- 了解IBD的遗传变异如何影响肠道微生物群的免疫耐受性.
- 阐明在IBD易感性背景下免疫细胞感知微生物信号的机制.
主要方法:
- 使用大肠炎和人类免疫细胞的小鼠模型.
- 研究了 Bacteroides fragilis OMV 和树突细胞之间的相互作用.
- 评估调节性T细胞 (Tregs) 对OMVs的反应.
- 研究了IBD风险基因ATG16L1和NOD2在OMV感应和Treg激活中的功能.
- 从具有ATG16L1风险变异的人体免疫细胞分析.
主要成果:
- OMV需要IBD相关的ATG16L1和NOD2基因来激活非正规的自途径以保护大肠炎.
- 缺少ATG16L1的树突细胞无法诱导抑制粘膜炎症的Tregs.
- 携带ATG16L1风险变异的人类免疫细胞对OMVs的Treg反应受损.
结论:
- 例如ATG16L1等IBD易感基因的遗传多态性可能导致检测保护性微生物信号的缺陷.
- 这些微生物信号传感缺陷会影响T细胞的调节反应,从而导致IBD的发病.
- 一个关键的基因环境相互作用,涉及宿主遗传和微生物组信号,被提出为IBD的关键病因.
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