Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China.
Kunming National High-level Biosafety Research Center for Non-Human Primates, Center for Biosafety Mega-Science, Kunming Institute of Zoology, Chinese Academic of Sciences, Kunming, Yunnan 650107, China.
Zool Res. 2020 Sep 18;41(5):517-526. doi: 10.24272/j.issn.2095-8137.2020.053.
The coronavirus disease 2019 (COVID-19) pandemic continues to pose a global threat to the human population. Identifying animal species susceptible to infection with the SARS-CoV-2/ HCoV-19 pathogen is essential for controlling the outbreak and for testing valid prophylactics or therapeutics based on animal model studies. Here, different aged Chinese tree shrews (adult group, 1 year old; old group, 5-6 years old), which are close relatives to primates, were infected with SARS-CoV-2. X-ray, viral shedding, laboratory, and histological analyses were performed on different days post-inoculation (dpi). Results showed that Chinese tree shrews could be infected by SARS-CoV-2. Lung infiltrates were visible in X-ray radiographs in most infected animals. Viral RNA was consistently detected in lung tissues from infected animals at 3, 5, and 7 dpi, along with alterations in related parameters from routine blood tests and serum biochemistry, including increased levels of aspartate aminotransferase (AST) and blood urea nitrogen (BUN). Histological analysis of lung tissues from animals at 3 dpi (adult group) and 7 dpi (old group) showed thickened alveolar septa and interstitial hemorrhage. Several differences were found between the two different aged groups in regard to viral shedding peak. Our results indicate that Chinese tree shrews have the potential to be used as animal models for SARS-CoV-2 infection.
新型冠状病毒病 2019（COVID-19）大流行继续对人类构成全球性威胁。鉴定易感染 SARS-CoV-2/HCoV-19 病原体的动物物种对于控制疫情以及基于动物模型研究测试有效的预防剂或疗法至关重要。在这里，不同年龄的中国树鼩（成年组，1 岁；老年组，5-6 岁），它们是灵长类动物的近亲，感染了 SARS-CoV-2。在不同的感染后天数（dpi）进行 X 射线、病毒脱落、实验室和组织学分析。结果表明，中国树鼩可以感染 SARS-CoV-2。在大多数感染动物的 X 射线照片中可见肺部浸润。在感染动物的肺组织中，3、5 和 7dpi 时始终检测到病毒 RNA，以及常规血液检查和血清生化相关参数的改变，包括天门冬氨酸氨基转移酶（AST）和血尿素氮（BUN）水平升高。对 3dpi（成年组）和 7dpi（老年组）动物肺组织的组织学分析显示肺泡间隔增厚和间质出血。在病毒脱落峰值方面，两个不同年龄组之间存在一些差异。我们的结果表明，中国树鼩有可能被用作 SARS-CoV-2 感染的动物模型。
