細胞毒性細胞は,グラヌリシン媒介によるグラン酵素の投与によって細胞内細菌を殺害する
Michael Walch1, Farokh Dotiwala1, Sachin Mulik1
1Cellular and Molecular Medicine Program, Boston Children's Hospital, Harvard Medical School, 200 Longwood Avenue, Boston, MA 02115, USA.
Cell
|June 7, 2014
まとめ
殺人細胞は,グラヌリシンを使用して,細菌にグラン酵素を送り込み,不可欠なタンパク質を損傷し,活性酸素種 (ROS) を生成することによって細胞死を誘発します. これは,新しい抗微生物防御機構を明らかにしています.
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:
- キラーリンパ球は,グラン酵素と呼ばれる細胞毒プロテアゼを使用して,感染した細胞を排除します.
- この過程における細胞内細菌の運命をよく理解していない.
- 人間の細胞毒性粒子は,ネズミでは見られない抗微生物ペプチドであるグラヌリシンを含んでいます.
研究 の 目的:
- 細菌の殺菌におけるグランウリシンとグラン酵素の役割を調査する.
- グラン酵素が細菌死を誘発するメカニズムを解明する.
主な方法:
- グラン酵素をバクテリアに配送するグラヌリシン媒介の配送を調査した.
- 細菌のタンパク質とEscherichia coli.の経路に対するグラン酵素の影響を分析した.
- ROSスキャベージャーの存在と変異した細菌のタンパク質で評価された細菌生存率.
- グラヌリシンを発現するトランスジェニックマウスにおけるバクテリアクリアランスの評価.
主要な成果:
- グランウリシンは,グラン酵素を様々な細菌株に提供し,細菌の死につながります.
- グラン酵素は,細菌の電子輸送連鎖複合体Iと酸化ストレスタンパク質を分裂させ,ROSを生成します.
- ROSの阻害または主要な細菌経路の破壊は,細菌の死亡を遅らせますが,予防しません.
- トランスジェニック・グラヌリシンを投与されたマウスは,Listeria monocytogenesのクリアランスが強化されたことを示した.
結論:
- グランウリシンは,グラン酵素媒介による細胞内細菌の殺戮を促進します.
- グラン酵素は,ROS生成と生命経路の障害を含む複数のメカニズムを通じて細菌の死を誘発します.
- 殺人細胞は,細菌に対する固有の強力な抗微生物機能を持っています.
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