毒素B对于Clostridium difficile的毒性至关重要
Dena Lyras1, Jennifer R O'Connor, Pauline M Howarth
1Australian Bacterial Pathogenesis Program, Department of Microbiology, Monash University, Victoria 3800, Australia.
Nature
|March 3, 2009
概括
Clostridium difficile B 毒素对于引起疾病至关重要,而不是毒素 A. 这一发现对于了解医院感染和开发新治疗方法至关重要.
科学领域:
- 微生物学 微生物学
- 传染性疾病 传染性疾病
- 胃肠病学 胃肠病学
背景情况:
- 困难菌是全球医院获得的传染性腹的主要原因.
- 增加的C. difficile相关疾病 (CDAD) 发病率和死亡率与高病毒性菌株和抗生素使用有关.
- 流行性NAP1/027菌株产生高水平的毒素A和B,这是关键的毒性因素.
研究的目的:
- 调查Clostridium difficile毒素A和B在疾病发病过程中的特定作用.
- 为了确定哪种毒素是自然感染期间的主要毒性决定因素.
主要方法:
- 在毒性C. difficile菌株中构建缺少tcdA和tcdB基因的同源突变.
- 使用仓鼠病模型来评估野生型和突变菌株的毒性.
- 与毒素A突变菌,毒素B突变菌和野生型菌株感染后的疾病结果进行比较.
主要成果:
- 鉴定出B毒素是C. difficile感染中必不可少的毒性决定因素.
- 单独的A毒素并没有在仓鼠模型中引起显著的病理,与此前使用净化毒素的研究相反.
- 毒素在疾病中的作用不能仅仅从使用净化毒素的研究中预测.
结论:
- 在感染期间,B毒素对C. difficile病毒性至关重要.
- 与净化毒素观察到的协同效应并不反映它们在自然感染中的作用.
- 在自然感染的背景下研究毒素对于了解疾病机制至关重要.
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