潜伏貯蔵庫の複製能力のある非誘導プロウイルスは,HIV-1を治すためのバリアを増やす
Ya-Chi Ho1, Liang Shan, Nina N Hosmane
1Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
Cell
|November 19, 2013
まとめ
潜伏するHIV-1プロウイルスは,休息しているCD4 (((+) T細胞に存在し,治癒を阻害する. 無傷で誘導されていないプロウイルスは複製能力があり,潜在貯蔵庫の推定サイズを大幅に増加させることが判明しました.
科学分野:
- ウイルス学 ウイルス学 ウイルス学
- 免疫学 免疫学とは
- 分子生物学は分子生物学である.
背景:
- 抗レトロウイルス療法 (ART) は,休息中のCD4 (〜+) T細胞に潜伏するプロウイルスが持続しているため,HIV-1感染を治すことはできません.
- T細胞の活性化により,潜伏中のプロウイルスの<1%が感染症ウイルスを放出し,非誘発のプロウイルスはしばしば欠陥があると推定されます.
研究 の 目的:
- 非誘導潜伏HIV-1プロウイルスの性質と複製能力を特徴付ける.
- 潜伏のHIV-1貯蔵庫の大きさと,治療の達成への影響を再評価する.
主な方法:
- 治療を受けたHIV-1患者からの213の非誘導プロバイラルクローンの分析.
- 直接的な配列決定とゲノム合成により,完全長さの無傷なプロウイルスクローンを再構築します.
- ロング・ターミナル・リピート (LTR) 機能とウイルスの成長動態の評価.
主要な成果:
- 誘導されていないプロウイルスクローンの11.7%は,正常なLTR機能を持つ無傷なゲノムを有しており,欠陥を含む88.3%とは対照的です.
- 再構築された無傷の非誘導プロウイルスには,誘導プロウイルスに匹敵する成長運動が示された.
- 非誘導プロウイルスは,非メチル化プロモーターを持つ活性転写ユニットに統合されていることが判明しました.
結論:
- 複製能力のある非誘導HIV-1プロウイルスは,潜伏貯蔵庫内に存在します.
- 潜伏するHIV-1の貯蔵庫は,以前に推定されたものより大幅に大きく,潜在的に最大60倍にもなる可能性があります.
- これらの無傷のプロウイルスの存在は,HIV-1の治癒に重大な障壁となっている.
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