Caspase-11は,バキュオールから脱出するバクテリアから保護します
Youssef Aachoui1, Irina A Leaf, Jon A Hagar
1Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
Science (New York, N.Y.)
|January 26, 2013
まとめ
Caspase-11は,宿主細胞の細胞溶液に侵入するバクテリアに対する先天的な免疫に不可欠です. この炎症性カスパースは,細菌のクリアランスを強化し,炎症性の経路から独立して感染から保護します.
科学分野:
- 免疫学 免疫学とは
- 微生物学 微生物学とは
- 細胞生物学 細胞生物学
背景:
- カスパスはアポトーシスと炎症の重要な調節体である.
- カスパース-1とカスパース-11を含む炎症性カスパースは,プログラム細胞死経路であるピロプトーシスを誘発する.
- カスパゼ-1は感染に対する保護的役割で知られているが,免疫におけるカスパゼ-11の機能は理解されていない.
研究 の 目的:
- バクテリアの病原体に対する先天的な免疫におけるカスパース-11の役割を調査する.
- 宿主細胞を侵略するバクテリアに対する防御にカスパース-11が不可欠であるかどうかを判断する.
主な方法:
- バクテリアの変異体 (Salmonella typhimurium sifA,Legionella pneumophila sdhA) を利用し,異常に宿主細胞の細胞溶液に侵入する.
- caspase-11の活性化と細菌のクリアランスを in vivoで評価した.
- 自然に生じる細胞性細菌 (ブルクホルデリア種) に反応するカスパース-11の役割を調べた.
- 炎症体経路の関与を調査した (NLRP3,NLRC4,ASC).
主要な成果:
- Caspase-11は,細胞性細菌に対する先天的な免疫のために必要ですが,真空細菌ではありません.
- S. typhimurium sifAとL. pneumophila sdhAの異常なサイトゾールエントリーは,カスパース-11を誘発した.
- Caspase-11は,S. typhimurium sifAのクリアランスを in vivoで強化した.
- サイトゾール性細菌に対するカスパゼ""媒介による保護は,NLRP3,NLRC4,ASC炎症体経路とは独立して発生した.
- Caspase-11は,Burkholderia種の致命的な挑戦から保護を与えました.
結論:
- カスパース-11は,細胞性細菌の病原体に対する天生的免疫において重要な役割を果たします.
- この経路は,細胞溶液に侵入する環境バクテリアに曝露した際の宿主の生存に不可欠です.
関連する概念動画
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