缺乏囊的A组菌在巨细胞中避免了自介导的杀死
Yong-An Shi1,2, Shiou-Ling Lu3, Takeshi Noda3,4
1Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, Taiwan.
mBio
|May 31, 2024
概括
群A型链球菌 (GAS) 囊缺乏症令人惊地提高了免疫细胞内的细菌存活率. 之前被认为有助于逃避的氨酸囊实际上是被巨细胞除的目标,这揭示了GAS病原发生的新作用.
科学领域:
- 微生物学 微生物学
- 免疫学 免疫学 免疫学
- 细胞生物学 细胞生物学
背景情况:
- 甲组链球菌 (GAS) 采用氨酸囊来保护其免受细胞杀死.
- 由囊缺乏的GAS菌株引起的疫情突出了了解免疫逃避机制的差距.
- 在细胞内病原体清除中GAS囊的作用仍然不完全理解.
研究的目的:
- 与野生型菌株相比,研究囊缺乏GAS突变体的细胞内生存机制.
- 阐明宿主细胞对GAS的识别和消除途径,重点关注囊的作用.
- 重新评估氨酸囊在巨细胞内GAS病原体中的功能.
主要方法:
- 从emm1 GAS菌株中产生一个囊缺陷突变 ([Cap(-)).
- 在细胞中对野生类型[Cap(+]和[Cap(-)]菌株存活率进行比较分析.
- 评估发酵体破坏,发酵体局部化和自性淘汰标记物 (盖莱克-8,乌比奎).
主要成果:
- 与野生型菌株相比,缺乏囊的GAS突变体在细胞中存活率增加.
- 这两种菌株都以类似的方式破坏了体,但只有野生型菌株局部化了 lysosomes.
- 缺乏囊的突变物逃避了加勒-8和无素的识别,从而损害了选择性自介导消除.
- 自适应蛋白识别了封装的GAS,但不是囊缺陷突变.
结论:
- GAS的氨酸囊被宿主巨细胞识别,并针对自性消除.
- 囊缺乏会影响巨细胞对GAS的细胞内清除,这与之前的假设相反.
- GAS囊在颠覆宿主免疫反应方面发挥着至关重要的作用,增强了菌细胞内的细菌存活率.
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