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Caspase-11は,非正規の炎症体シグナル伝達のためにガスダーミンDを割る
Nobuhiko Kayagaki1, Irma B Stowe1, Bettina L Lee1
1Department of Physiological Chemistry, Genentech Inc., South San Francisco, California 94080, USA.
Nature
|September 17, 2015
まとめ
ガスダーミンD (GSDMD) は,グラム陰性細菌感染後のカスパーゼ""誘発の熱中症とインタールキン"βの放出に不可欠です. カスパース-11によるGSDMDの活性化は,致命的な細菌性毒に対する宿主防御を媒介する.
科学分野:
- 免疫学
- 細胞生物学
- 微生物学
背景:
- グラム陰性細菌からの細胞内リポポリサッカライドは,カスパース11を誘発し,ピロプトーシス,IL-1β処理,そしてセプティックショックを引き起こす.
- カスパース-11の正確な下流信号伝達経路は,ほとんど解明されていない.
研究 の 目的:
- カスパース""依存細胞死とサイトカイン成熟の鍵となるメディエーターを特定する.
- 細胞内グラム陰性細菌成分に対する宿主反応におけるガスダーミンDの役割を解明する.
主な方法:
- エチル-N-ニトロ尿素変異したマウスを用いて遺伝子スクリーニングを進めます.
- Gsdmdノックアウト (Gsdmd(-/-)) マウスを生成するための遺伝子ターゲティング.
- マクロファージの熱死とIL-1β分泌の分析
- リポポリサッカライド試験後のマウスの生存率の評価
主要な成果:
- ガスダーミンD (Gsdmd) は,カスパーゼ""媒介の炎症とIL- 1βの成熟に不可欠であると特定されました.
- Gsdmd ((-/-) マクロファージは,細胞質のリポポリサッカリドまたはグラム陰性細菌で刺激されたときに,欠陥のあるピロプトーシスおよびIL-1β分泌を示した.
- Gsdmd ((-/-) マウスは,致死性量のリポポリサッカリドから保護された.
- カスパース-11はガスダーミンDを直接裂き,N端の断片は熱滅亡を引き起こし,カスパース-1/NLRP3炎症体を活性化する.
結論:
- ガスダーミンDは生まれながらの免疫応答におけるカスパース-11の重要な下流標的である.
- ガスダーミンDは,炎症とIL- 1βの生成を媒介し,グラム陰性細菌感染症に対する宿主防御に不可欠です.
- カスパース-11-ガスダーミンD軸は,細菌性毒に対する宿主防御における重要な経路を表しています.
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