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bioRxiv · 10.1101/2020.02.07.939389

The Pathogenicity of 2019 Novel Coronavirus in hACE2 Transgenic Mice

Abstract

Severe acute respiratory syndrome CoV-2 (SARS-CoV-2) caused the Corona Virus Disease 2019 (COVID-19) cases in China has become a public health emergency of international concern (PHEIC). Based on angiotensin converting enzyme 2 (ACE2) as cell entry receptor of SARS-CoV, we used the hACE2 transgenic mice infected with SARS-CoV-2 to study the pathogenicity of the virus. Weight loss and virus replication in lung were observed in hACE2 mice infected with SARS-CoV-2. The typical histopathology was interstitial pneumonia with infiltration of significant lymphocytes and monocytes in alveolar interstitium, and accumulation of macrophages in alveolar cavities. Viral antigens were observed in the bronchial epithelial cells, alveolar macrophages and alveolar epithelia. The phenomenon was not found in wild type mice with SARS-CoV-2 infection. The pathogenicity of SARS-CoV-2 in hACE2 mice was clarified and the Kochs postulates were fulfilled as well, and the mouse model may facilitate the development of therapeutics and vaccines against SARS-CoV-2.

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Bao, L., Deng, W., Huang, B., Gao, H., Ren, L., Wei, Q., Yu, P., Xu, Y., Liu, J., Qi, F., Qu, Y., Wang, W., Li, F., Lv, Q., Xue, J., Gong, S., Liu, M., Wang, G., Wang, S., Zhao, L., Liu, P., Ye, F., Wang, H., Zhou, W., Zhu, N., Zhen, W., Yu, H., Zhang, X., Song, Z., Guo, L., Chen, L., Wang, C., Wang, Y., Wang, X., Xiao, Y., Sun, Q., Liu, H., Zhu, F., Ma, C., Yan, L., Yang, M., Han, J., Xu, W., Tan, W., Peng, X., Jin, Q., Wu, G., Qin, C.. 2020-02-11. The Pathogenicity of 2019 Novel Coronavirus in hACE2 Transgenic Mice. https://doi.org/10.1101/2020.02.07.939389

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