トール型受容体-2は,リポポリサカライド誘発の細胞シグナル伝達を媒介する
1Department of Molecular Biology, Genentech, South San Francisco, California 94080-4990, USA.
Nature
|September 29, 1998
まとめ
トール型受容体2 (TLR2) は,グラム陰性細菌からのリポポリサッカリド (LPS) の重要なセンサーとして作用します. この発見は,TLR2がLPSに対する細胞応答の直接的な仲介者であり,免疫防御に不可欠であることを明らかにしています.
科学分野:
- 免疫学 免疫学とは
- 細胞生物学 細胞生物学
- 微生物学 微生物学とは
背景:
- グラム陰性細菌は,細胞壁にリポポリサッカリド (LPS) を含んでおり,脊椎動物と無脊椎動物の防御機構を誘発する.
- 人間のモノサイトとマクロファージは,LPSに反応して,サイトカインやその他の炎症媒介物質を産生しますが,信号伝達機構は不明でした.
- LPSの暴露は,生命を脅かす状態であるセプティックショックを引き起こし,LPSの感知を理解する必要性を強調します.
研究 の 目的:
- リンポポリサッカライド (LPS) 信号伝導のメカニズムをプラズマ膜を通して解明する.
- ミエロイド細胞におけるLPSシグナル伝達を媒介する特定の受容体を特定する.
主な方法:
- LPS感知におけるトール型受容体2 (TLR2) の役割を調査した.
- LPS結合タンパク質 (LBP) とCD14に対するTLR2活性化の依存性を調べました.
- IL-1受容体とのホモロジーについてTLR2の細胞内信号領域を分析した.
主要な成果:
- Toll-like receptor 2 (TLR2) は,LPS.によって活性化されたシグナル伝達受容体として特定されました.
- LPSによるTLR2活性化は,LPS結合タンパク質 (LBP) に依存し,CD14によって強化された.
- IL-1受容体と同型であるTLR2の特定の細胞内領域は,応答に不可欠であることが判明しました.
結論:
- トール型受容体2 (TLR2) は,リポポリサッカリド (LPS) によって開始されたシグナル伝達を直接媒介する.
- この発見は,グラム陰性細菌感染症に対する先天的な免疫応答の重要なステップを明らかにします.
- LPSの感知におけるTLR2の役割を理解することは, септикショックのような状態の管理に意味を持っています.
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