SARS-CoV-2の減弱された複製と病原性 B.1.1.529 オミクロン
Huiping Shuai1, Jasper Fuk-Woo Chan1, Bingjie Hu1
1State Key Laboratory of Emerging Infectious Diseases, Department of Microbiology, and Carol Yu Centre for Infection, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, Hong Kong, People's Republic of China.
Nature
|January 21, 2022
まとめ
SARS-CoV-2のオミクロン変種は,マウスにおける複製と病原性の低下を示しています. この重症急性呼吸器症候群コロナウイルス2型は,肺の病態が弱まり,死亡率は他の株と比較して低い.
科学分野:
- ウイルス学
- 病理学について
- 免疫学
背景:
- オミクロン (B.1.1.529型) のSARS-CoV-2は2021年11月に急速に発生した.
- オミクロンは中和抗体からの免疫脱出を示していますが,その病原性はよく理解されていません.
研究 の 目的:
- SARS-CoV-2 オミクロン変種の病原性および複製効率を調査する.
- オミクロンの特性を野生型SARS-CoV-2や他の変種と比較する.
主な方法:
- ヒトのCalu3およびCaco2細胞におけるin vitro複製試験
- オミクロン,ワイルド型,デルタ型,アルファ型,ベータ型に感染したK18- hACE2マウスを用いた体内試験.
- 呼吸道におけるウイルスの複製,肺病変,体重減少,死亡率の評価.
主要な成果:
- Omicronの複製はヒトの肺細胞 (Calu3, Caco2) とK18- hACE2マウスの呼吸道で著しく弱まった.
- オミクロンは,他のSARS-CoV-2株と比較して,トランスメブランセリンプロテアゼ2 (TMPRSS2) の非効率的な使用を示した.
- オミクロンによる感染は,肺の病態が著しく改善され,体重が減少し,野生型および他の変種と比較してマウスの死亡率が低かった.
結論:
- オミクロン変種は,体内での複製と病原性の低下を示しています.
- TMPRSS2の利用率の低下は,オミクロンの弱まった表型に寄与する可能性があります.
- オミクロンは,以前のSARS-CoV-2変種と比較してマウスモデルでより軽度の疾患プロファイルを示しています.
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