MHC/HLA-Iを受容体として持つ新興の腸球胞胞形成毒素
Xiaozhe Xiong1, Songhai Tian1, Pan Yang2
1Department of Urology, Boston Children's Hospital, Department of Surgery, Harvard Medical School, Boston, MA 02115, USA; Department of Microbiology, Harvard Medical School, Boston, MA 02115, USA.
Cell
|March 8, 2022
まとめ
研究者達は,多剤耐性感染症を引き起こす エントロコックスの毛穴形成毒素 (Epxs) を発見した. これらの毒素はヒト白血球抗原クラスI (HLA-I) 複合体を標的とし,Enterococcusにおける新しい毒性のメカニズムを強調しています.
科学分野:
- 微生物学
- 免疫学
- 構造生物学
背景:
- エントロコックは共生細菌であり,多剤耐性感染症の重要な源です.
- 毛穴形成毒素 (PFT) は多くの細菌病原体にとって重要な毒性因子です.
研究 の 目的:
- エントロコックスの新種の毛穴形成毒素を特定し,特徴づけること.
- Enterococcus媒介による病原性と宿主細胞の相互作用を明らかにする.
主な方法:
- 毒素受容体を特定するための全ゲノムCRISPR-Cas9スクリーニング
- 毒素構造を決定する構造生物学技術
- 毒素誘発性細胞毒性を評価するための細胞ベースの測定法とオルガノイドモデル.
- 細菌の毒性を評価するためのインビトロ共同培養実験.
主要な成果:
- 全球株のE. faecalis,E. faecium,E. hiraeで新しいEnterococcus孔形成毒素 (Epxs) が特定されました.
- Epx毒素は独特のβバレル構造を持ち,明確なトップドメインを持っています.
- ヒト白血球抗原クラスI (HLA- I) は,Epx2およびEpx3の受容体として特定され,ヒトおよび特定の動物のMHC- I分子に優先的に結合するが,ネズミには結合しない.
- インターフェロン治療はEpx2とEpx3に対する細胞の感受性を高めました.
- Epx2を生成するEnterococcus faeciumは,ヒト外周血液の単核細胞と腸内臓器官を損傷し,Epx2抗体によって毒性が中和された.
結論:
- エントロコックスの毛穴形成毒素 (Epxs) は,新たに特定された細菌の毒性因子の一種である.
- HLA-I複合体とのEpx毒素の相互作用は,宿主の免疫を回避し,病気を引き起こすためのメカニズムを提供します.
- Epx毒素を標的とすることは,多剤耐性エンテロコックスの感染に対する潜在的な治療戦略を提供します.
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