减弱的SARS-CoV-2复制和致病性 B.1.1.529 奥米克朗
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
概括
SARS-CoV-2 的 Omicron 变种在小鼠中显示出减少的复制和致病性. 与其他菌株相比,这种严重急性呼吸综合征冠状病毒2型呈现衰弱的肺病理和较低的死亡率.
科学领域:
- 病毒学
- 病理学
- 免疫学
背景情况:
- 在2021年11月,SARS-CoV-2的Omicron (B.1.1.529) 变种迅速出现.
- 虽然Omicron证明了免疫从中和抗体中逃脱,但其致病性尚未得到充分了解.
研究的目的:
- 调查SARS-CoV-2 Omicron变种的致病性和复制效率.
- 将Omicron的特征与野生型SARS-CoV-2和其他变种进行比较.
主要方法:
- 在人体Calu3和Caco2细胞中进行体外复制试验.
- 使用K18-hACE2感染Omicron,野生型,Delta,Alpha和Beta变体的小鼠进行体内研究.
- 对呼吸道病毒复制,肺病理,体重减轻和死亡率的评估.
主要成果:
- 在人类肺细胞 (Calu3,Caco2) 和K18- hACE2小鼠的呼吸道中,Omicron复制显著减弱.
- 与其他 SARS-CoV-2 菌株相比,Omicron 显示了跨膜血清蛋白酶 2 (TMPRSS2) 的低效使用.
- 与野生型和其他变种相比,感染Omicron导致肺部病理明显改善,体重减少最少,死亡率最低.
结论:
- 在体内,Omicron变种表现出减弱的复制和致病性.
- 减少TMPRSS2的利用可能导致Omicron的减弱表型.
- 与之前的SARS-CoV-2变种相比,Omicron在小鼠模型中呈现出较少严重的疾病特征.
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