对于沙门氏菌 typhimurium 毒性,需要提供 TLR 信号
Nicholas Arpaia1, Jernej Godec, Laura Lau
1Division of Immunology & Pathogenesis, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720-3200, USA.
Cell
|March 8, 2011
概括
收费类受体 (TLRs) 对于控制沙门氏杆菌感染至关重要. 来自TLRs的先天免疫线索调节了细菌毒性基因,这对于生存和系统传播至关重要.
科学领域:
- 免疫学 免疫学 免疫学
- 微生物学 微生物学
- 遗传学 是一个遗传学.
背景情况:
- 收费类受体 (TLRs) 在对抗微生物病原体的宿主防御中起着关键作用.
- TLRs可以影响病原体毒性机制的演变.
- 沙门氏菌 (Salmonella typhimurium) 是一种细胞内细菌病原体,会引起系统性感染.
研究的目的:
- 研究宿主耐药性和病原体毒性之间的关系.
- 为了检查托尔类受体 (TLRs) 在控制沙门氏菌 typhimurium 感染中的作用.
- 了解天生的免疫系统线索如何调节细菌毒性基因表达.
主要方法:
- 使用具有功能性nramp-1基因并缺乏托尔类受体 (TLRs) 组合的小鼠.
- 感染了沙门氏菌 Typhimurium 的小鼠.
- 评估了TLR缺乏细胞中的细菌负载,毒性基因表达 (SPI-2) 和细胞酸化.
主要成果:
- 缺少TLR2和TLR4的小鼠对沙门氏甲型杆菌 (Salmonella typhimurium) 的高度敏感.
- 缺乏参与病原体识别的额外TLRs的小鼠表现出敏感性降低.
- 沙门氏甲状病毒未能提高SPI-2基因的调节,并在TLR缺陷细胞中形成可复制的组件.
- TLR信号增强了体酸化,这是SPI-2诱导所必需的.
结论:
- 沙门氏菌需要来自TLRs介导的先天免疫系统的线索来调节毒性基因.
- 通过TLR介导的细胞体酸化对于细菌细胞内生存,生长和系统性感染至关重要.
- 了解这种相互作用可以为打击细菌感染的策略提供信息.
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