スパイク変異D614GはSARS-CoV-2の適応性を変化させる
Jessica A Plante1,2,3, Yang Liu4, Jianying Liu2,3
1World Reference Center for Emerging Viruses and Arboviruses, University of Texas Medical Branch, Galveston, TX, USA.
Nature
|October 27, 2020
まとめ
SARS-CoV-2 D614G スパイクタンパク質の変異は,ウイルスの複製と拡散を促進します. この変種はCOVID-19に対するワクチンの有効性を著しく低下させる可能性は低いが,治療用抗体は検査を必要とする.
科学分野:
- ウイルス学
- 感染症
- ワクチン学
背景:
- SARS-CoV-2のスパイクタンパク質のD614G置換は,COVID-19のパンデミック中に支配的な変種となった.
- D614G変種がウイルスの伝播と既存のワクチンの有効性に与える正確な影響は不明でした.
研究 の 目的:
- SARS-CoV-2 D614Gスパイクタンパク質変異の機能的効果を調査する.
- ウイルスの拡散,感染性,ワクチンによる免疫に対するD614G変異の影響を評価する.
主な方法:
- USA-WA1/2020 SARS-CoV-2 株にD614G スパイクタンパク質の置換を設計した.
- ヒトの肺上皮細胞と呼吸道組織でウイルスの複製を評価した.
- 野生型 (D614) および変異型 (G614) ウイルスに感染したハムスターと測定されたウイルス負荷.
- D614とG614の両方のウイルスに対するハムスター血清の中和活性評価.
主要な成果:
- D614Gの置換は,ウイルスの感染性と安定性を高め,ヒトの肺細胞と呼吸道組織におけるウイルスの複製を強めた.
- G614ウイルスは感染したハムスターの上部呼吸道 (鼻洗い,気管) でより高い感染チーターを生成したが,肺は生じなかった.
- D614ウイルスに感染したハムスターの血清は,D614ウイルスと比較してG614に対する中和度がわずかに高かった.
結論:
- D614G変異は,上部呼吸道におけるウイルスの増加に大きく寄与し,SARS-CoV-2の伝播を促進します.
- D614G変種は,以前のSARS-CoV-2株に対して開発されたワクチンの保護効果を大幅に低下させる可能性は低い.
- 治療用抗体は,現在流通しているG614変種に対して評価され,COVID-19の治療の有効性を確保する必要があります.
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