毒素Aと毒素Bがクロストリジウム・ディフィシル感染における役割
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
まとめ
クラストリジウムディフィシル毒素AとBは,感染を引き起こすために不可欠です. この研究は,いずれかの毒素が単独で重篤な疾患を引き起こす可能性があることを実証し,C. difficile感染における個々の重要性を再確立しました.
科学分野:
- 微生物学 微生物学とは
- 感染症 感染症は感染症です.
- 胃腸内科 胃腸内科
背景:
- クラストリジウムディフィシル感染症 (CDI) は,医療関連の下痢の主要な原因です.
- 毒素AとBは主要な毒性の要因ですが,CDIの病原性における個々の役割については議論されています.
- 以前の研究では,C. difficileの毒性に対するB毒素の必要性に関する矛盾する証拠が提示されました.
研究 の 目的:
- クロストリジウム・ディフィシル毒素AとBの個別の重要性に関するパラドックスを解明する.
- イソジェニック変異体を用いて,C. difficile感染における各毒素の役割を調査する.
- 関連する動物モデルにおけるC. difficileの毒性に対する両方の毒素の必要性を決定する.
主な方法:
- 毒素Aまたは毒素Bを単独で生成する同位性のClostridium difficile変異体の構築.
- 毒素Aと毒素Bの両方の遺伝子が欠けている二重変異株の生成.
- 生成された変異体の in vitro 細胞毒性活性の評価.
- ハムスターの感染モデルにおけるC. difficileの毒性の評価.
主要な成果:
- 毒素Aまたは毒素Bを単独で生成するクロストリジウム・ディフィシル (Clostridium difficile) は,ハムスターに fulminant 疾患を引き起こしました.
- 毒素を産生する突然変異体のインビトロ細胞毒性活動は,インビボの毒性と直接相関していた.
- 両方の毒素を欠いた二重変異株は,完全に毒性の高いもので,両方の毒素の本質性を確認しました.
結論:
- クラストリジウム・ディフィシル・トキシンAとトキシンBはそれぞれ,重症な病気を引き起こす能力があります.
- この発見は,C. difficileの病原化における両方の毒素の重要な役割を再確立しています.
- 毒素Aと毒素Bの両方が,CDIの診断と治療の開発において考慮されるべきである.
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