结核菌的MDA5RNA感应通路激活促进了先天免疫颠覆和病原体生存
JCI insight
|September 19, 2023
概括
类似RIG-I的受体MDA5感知了Mycobacterium结核病RNA,促进了细菌的生长. 消除MDA5可以增强巨细胞的免疫反应和对结核病的宿主生存.
科学领域:
- 免疫学 免疫学 免疫学
- 微生物学 微生物学
- 细胞生物学 细胞生物学
背景情况:
- 通过RIG-I类受体 (RLRs) 对Mycobacterium tuberculosis (M. tuberculosis) RNA的宿主细胞质感应会影响巨细胞中的先天免疫控制.
- 作为RLR家族成员的MDA5在M.结核病的发病过程中的特定作用需要进一步阐明.
研究的目的:
- 确定MDA5在M.结核病原体中的作用.
- 评估野生型 (WT) 和Mda5淘汰 (Mda5-/-) 巨细胞中M.结核病细胞内生长和先天免疫反应.
主要方法:
- 在WT和Mda5-/-巨细胞中比较了M.结核病细胞内生长和细胞因子的产生.
- 在M.结核病感染期间评估MDA5蛋白表达和激活 (多重形成).
- 在小鼠结核病模型中评估宿主存活率和细菌负担.
主要成果:
- 结核病M.结核病RNA转染诱导了WT中的前炎性细胞因子,但不是Mda5-/-巨细胞.
- 结核病感染上调了MDA5的表达和激活.
- Mda5-/-巨细胞对细胞内M.结核病的控制有所增强,自性增加,IL-1β产生减少.
- 缺乏Mda5为宿主生存带来了好处,并在体内减少了细菌负载.
结论:
- 通过促进细菌生长和免疫逃避,MDA5在宿主防御M.结核病中起着有害的作用.
- 失去MDA5是宿主保护性的,这表明M.结核病利用MDA5颠覆免疫制.
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