毒素A和毒素B在Clostridium difficile感染中的作用
Sarah A Kuehne1, Stephen T Cartman, John T Heap
1Clostridia Research Group, Centre for Biomolecular Sciences, School of Molecular Medical Sciences, Nottingham Digestive Diseases Centre, NIHR Biomedical Research Unit, University of Nottingham, Nottingham NG7 2RD, UK.
Nature
|September 17, 2010
概括
困难菌毒素A和B都对引起感染至关重要. 这项研究表明,单独的任何一种毒素都可能导致严重的疾病,这重新确立了它们在C. difficile感染中的个人重要性.
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:
- 困难菌感染 (CDI) 是与医疗保健相关的腹的主要原因.
- 毒素A和B是关键的毒性因素,但它们在CDI病变发生过程中的个别作用一直受到争议.
- 之前的研究提出了相互矛盾的证据,关于毒素B对C. difficile病毒性的必要性.
研究的目的:
- 解决关于Clostridium difficile毒素A和B的个体重要性悖论.
- 用同位素突变物研究每种毒素在C. difficile感染中的作用.
- 确定相关动物模型中对C. difficile毒性的两种毒素的必要性.
主要方法:
- 构建同源的Clostridium difficile突变,单独产生毒素A或毒素B.
- 产生一种双重突变菌株,缺乏毒素A和毒素B基因.
- 评估产生的突变体的体外细胞毒性活性.
- 在感染的仓鼠模型中评估C. difficile毒性.
主要成果:
- 困难菌产生毒素A或毒素B,单独导致子发病.
- 产生毒素的突变体在体内细胞毒性活性与体内毒性直接相关.
- 缺少这两种毒素的双重突变菌株是完全有毒的,证实了这两种毒素的基本性.
结论:
- 无论是Clostridium difficile毒素A还是毒素B,都能够单独引起严重的疾病.
- 这些发现重新确立了这两种毒素在C. difficile病变发生过程中的关键作用.
- 在开发CDI的诊断和治疗时,应考虑A和B毒素.
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