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Static Adhesion Assay for the Study of Integrin Activation in T Lymphocytes
Published on: June 13, 2014
细菌劫持整合素结合激酶以稳定焦点粘附并阻止细胞脱离
Minsoo Kim1, Michinaga Ogawa, Yukihiro Fujita
1Department of Infectious Disease Control, International Research Center for Infectious Diseases, University of Tokyo, 4-6-1, Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
Nature
|June 3, 2009
概括
石格拉细菌使用OspE蛋白来增强宿主细胞的粘附,防止在感染期间上皮细胞脱离. 这种与整合素连接激酶 (ILK) 的相互作用有助于细菌保持其传染性立足点.
科学领域:
- 微生物学 微生物学
- 细胞生物学 细胞生物学
- 传染性疾病 传染性疾病
背景情况:
- 粘膜上皮细胞自然脱落以防止细菌感染.
- 像Shigella这样的致病细菌可以克服这种防御,以殖民上皮质.
- 了解细菌对宿主细胞粘附的策略,对于对抗感染至关重要.
研究的目的:
- 研究Shigella flexneri效应物OspE促进细菌殖民的机制.
- 阐明OspE与宿主细胞蛋白质整合因酶 (ILK) 相互作用在细菌粘附和生存中的作用.
主要方法:
- 研究了Shigella flexneri OspE和宿主整合素结合激酶 (ILK) 之间的相互作用.
- 分析了焦点粘附的变化,整合素水平,以及焦点粘附激酶和帕克西林的酸化.
- 使用诺可达-洗试验来评估焦点粘附分解.
- 在被野生型Shigella和 ospE突变病毒感染的两极化上皮细胞中比较细胞脱落.
- 感染了西格拉菌的几内亚猪结肠,以评估OspE-ILK相互作用的体内作用.
主要成果:
- 西格拉 OspE 结合宿主 ILK,增加焦点粘附和膜结合的 ILK.
- OspE-ILK相互作用提高了细胞表面1整体,并减少了焦点粘附周转率.
- OspE阻断了诺可达洗诱导的焦点粘附分解.
- 与野生类型相比,Shigella ospE突变体表现出增加的上皮细胞脱落.
- 在体内,OspE-ILK相互作用抑制了上皮脱落,增强了细菌的传播,并促进了殖民.
结论:
- 石格拉利用OspE效应器结合ILK,增强宿主细胞的附着性,并防止上皮细胞脱离.
- 这种机制使Shigella能够保持稳定的传染性立足点,并促进殖民.
- OspE-ILK相互作用是Shigella抑制宿主防御的关键毒性因素.
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