トリプトファン生物合成は,ミコバクテリアをCD4T細胞媒介による殺戮から保護する
Yanjia J Zhang1, Manchi C Reddy, Thomas R Ioerger
1Department of Immunology and Infectious Disease, Harvard School of Public Health, Boston, MA 02115, USA.
Cell
|December 10, 2013
まとめ
結核菌 (Mycobacterium tuberculosis,Mtb) は,トリプトファンを合成することで,免疫防御を回避する. この合成を阻害すると,Mtbはトリプトファンオクストロフに変換され,宿主の免疫に敏感になり,新しい治療法への道が開きます.
科学分野:
- 微生物学 微生物学とは
- 免疫学 免疫学とは
- ドラッグ・ディスカバリー・ドリッグ・ディスカバリー・ドリッグ・ディスカバリー・ドリッグ・ディスカバリー
背景:
- 病原性細菌は,宿主の免疫反応を克服するメカニズムを持っています.
- これらの細菌の生存戦略を理解することは,効果的な治療法の開発に不可欠です.
研究 の 目的:
- マイコバクテリアの結核 (Mtb) が宿主の免疫を生き残るための細菌の遺伝子 (対抗菌) を特定する.
- Mtbのレジスタンスメカニズムを理解することによって,新しい治療目標を探求する.
主な方法:
- Mtbのゲノムスケール分析により,対抗アクトームを特定する.
- Mtbの生存におけるトリプトファン代謝の役割を調査する.
- Mtbのトリプトファン合成経路の小分子阻害剤のスクリーニング.
主要な成果:
- CD4T細胞は,トリプトファン飢餓によってMtbを制御しようとしますが,これはMtbに対して効果のないメカニズムです.
- Mtbはストレス下ではトリプトファンを合成し,宿主による飢餓を回避します.
- Mtbトリプトファンの合成を阻害する新しい小分子阻害剤が特定され,トリプトファンのオクスオトロフと化しました.
結論:
- トリプトファンを合成するMTBの能力は,その免疫回避の重要な要因です.
- Mtbのトリプトファン合成経路をターゲットにすると,宿主の防御効果が回復します.
- Mtb counteractomesは,新しい抗感染症治療法の発見を導くことができます.
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