バクテリア外膜膀はLPSとCaspase-11の局所化を媒介する

Sivapriya Kailasan Vanaja¹, Ashley J Russo¹, Bharat Behl¹

¹Department of Immunology, UConn Health School of Medicine, 263 Farmington Avenue, Farmington, CT 06030, USA.

Cell

|May 10, 2016

まとめ

外膜膀 (OMV) はリポポリサカライド (LPS) を宿主細胞細胞溶液に放出し,カスパース11を活性化する. このメカニズムは,グラム陰性細菌と敗血症の病原性に対する宿主の防御に不可欠です.

科学分野:

免疫学
微生物学
細胞生物学

背景:

細胞性リポポリサカリド (LPS) によるカスパース - 11の活性化は,グラム陰性細菌と敗血症に対する宿主防御に不可欠です.
非細胞性グラム陰性細菌によるLPSの細胞溶液への侵入のメカニズムは不明である.

研究の目的:

LPSが宿主細胞の細胞溶液にアクセスし,カスパース-11の活性化を誘発するメカニズムを解明する.

主な方法:

LPS転位における外膜小胞 (OMVs) の役割を調査した.
in vitroおよびin vivoモデルを使用した.
OMVの機能を評価するために低血管性細菌変異体を使用した.

主要な成果:

主体細胞の細胞溶液にLPSを供給する主要な媒介としてOMVを特定した.
初期エンドソームからLPSが放出され,エンドサイトーシスによるOMV内化が実証された.
OMV生産に欠陥のある細菌変異体を使用して,LPS細胞局所化を媒介するOMVの重要な役割が確認されました.

結論:

外膜膀 (OMVs) は,宿主細胞の細胞溶液へのLPSの侵入の重要な媒介体である.
OMV媒介によるLPSの投与はカスパース11の活性化を引き起こし,宿主の防御と敗血症に影響を与えます.
この研究は,グラム陰性細菌の感知と宿主の免疫反応の鍵となる経路を示しています.

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