カスパーゼ-1アダプターASCとIPAFによる炎症体の微分活性化
Sanjeev Mariathasan1, Kim Newton, Denise M Monack
1Molecular Oncology Department, Genentech, Inc., 1 DNA Way, South San Francisco, California 94080, USA.
Nature
|June 11, 2004
まとめ
アダプタASCは,炎症体の活性化およびその後のIL-1β/IL-18の成熟に不可欠です. Ipafは特に細胞内病原体によるカスパース-1の活性化を媒介し,炎症と細胞死経路に影響を与えます.
科学分野:
- 免疫学 免疫学とは
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
背景:
- イニシエーターカスパスは,FADDやApaf-1のような特定のアダプターによって制御されます.
- ASC,IPAF,RIP2などのアダプタを含む炎症体複合体は,カスパゼ-1 (インタールイキン-1変換酵素) を活性化します.
研究 の 目的:
- 炎症ゾーム機能におけるASC,IPAF,RIP2アダプターの役割を調査する.
- これらのアダプタがカスパーゼ-1の活性化と下流の炎症反応に与える特定の貢献を明らかにする.
主な方法:
- 遺伝子欠乏マクロファージ (ASC-,Ipaf-,RIP2-null) とマウスを利用した.
- 細胞外ATP,トール型受容体 (TLR) アゴニスト,細胞内病原体 (Salmonella typhimurium) による刺激されたマクロファージ.
- カスパース-1の活性化,IL-1βおよびIL-18の成熟,内毒性ショックへの耐性,および病原体誘発細胞死を評価した.
主要な成果:
- ASC欠乏症は,細胞外ATP駆動のカスパース-1活性化,IL-1β/IL-18成熟,および内毒性ショックを無効にしました.
- ASC-nullマクロファージは,S. typhimuriumに対する反応として,カスパゼ-1の活性化が深刻に低下したことを示した.
- IPAF欠乏症では,S. typhimuriumによるカスパース-1活性化が低下するが,TLRとATPの刺激による活性化には影響しない.
- RIP2の欠乏は,カスパース-1の活性化を損ねなかった.
- カスパーゼ-1を誘発する刺激によって引き起こされたマクロファージ細胞死は,ASCまたはIPAF欠乏細胞で廃止されました.
結論:
- ASCは,炎症性シトカインの成熟と宿主防御に不可欠な炎症体媒介のカスパース-1活性化に不可欠です.
- Ipafは,細胞内病原体による炎症体の活性化のための特定の経路として作用します.
- ASCとIpaf.によって媒介される炎症ゾーム媒介の炎症と細胞死経路の間に重要な関連性があります.
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