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Invasion of Human Cells by a Bacterial Pathogen
Published on: March 21, 2011
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グループA ストレプトコッカスは,CD44媒介細胞シグナル伝達によって組織を侵略する.
1Channing Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.
Nature
|December 12, 2001
まとめ
Streptococcus pyogenesは,そのヒアルロン酸カプセルを使用して宿主分子を模倣し,細胞の形状の変化と侵入を誘発します. 皮質細胞のCD44との相互作用は,パラセルラー経路を通って細菌の侵入を容易にする.
科学分野:
- 微生物学 微生物学とは
- 細胞生物学 細胞生物学
- パトジェネシス (病原生)
背景:
- ストレプトコッカス・ピオゲネス (A群のストレプトコッカス,GAS) は,喉頭と皮膚の感染症を引き起こす.
- GASは,そのヒアルロン酸カプセルを使用して,ヒトの上皮細胞のCD44受容体と結合します.
- この結合相互作用は,バクテリアの結合と,その後の宿主細胞の操作に極めて重要です.
研究 の 目的:
- GASヒアルロン酸カプセルのCD44の分子模倣が細胞反応を誘発するかどうかを調査する.
- GASが宿主組織に侵入するメカニズムを解明する.
主な方法:
- ヒトケラチノシートの単層に結合するCD44依存のGASを研究した.
- 細胞骨格の再編成,細胞間結合の破壊,信号伝導経路 (Rac1,エズリン,チロシンリン酸化) を分析した.
- 人間の皮膚モデルにおけるバクテリアの転位を調べた.
主要な成果:
- GASがCD44に結合すると,膜ラッフリングを含む,ケラチノシートの重要な細胞骨格変化が誘発された.
- 細胞間結合が破壊され,バクテリアの通過が容易になりました.
- Rac1,エズリン,チロシンリン酸化を含む信号伝導が,これらの細胞応答を媒介した.
- 人間の皮膚モデルを通じたGASの転位は,CD44媒介のシグナル伝達によって有効化されたパラセルラー経路を経由して発生しました.
結論:
- GASは,CD44媒介の分子模倣によって宿主細胞の細胞骨格を操作する.
- このメカニズムは,パラセルラー経路を通じて細菌の組織侵入を促進します.
- この発見は,宿主細胞骨格の操作と細胞外病原菌による侵入のモデルを提供します.
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