Menzies Health Institute Queensland, Griffith University, Gold Coast Campus, Southport, Queensland, Australia.
Global Virus Network (GVN) Centre of Excellence in Arboviruses, Griffith University, Gold Coast, QLD, Australia.
mBio. 2021 Apr 20;12(2):e00819-21. doi: 10.1128/mBio.00819-21.
Newly emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the ongoing coronavirus disease 2019 (COVID-19) pandemic, which has caused extensive mortality and morbidity and wreaked havoc on socioeconomic structures. The urgent need to better understand SARS-CoV-2 biology and enable continued development of effective countermeasures is aided by the production of laboratory tools that facilitate SARS-CoV-2 research. We previously created a directly accessible SARS-CoV-2 toolkit containing user-friendly reverse genetic (RG) infectious clones of SARS-CoV-2. Here, using K18-human ACE2 (hACE2) mice, we confirmed the validity of RG-rescued SARS-CoV-2 viruses to reproduce the infection profile, clinical disease, and pathogenesis already established in mice infected with natural SARS-CoV-2 isolates, often patient derived. RG-rescued SARS-CoV-2-infected K18-hACE2 mice developed substantial clinical disease and weight loss by day 6 postinfection. RG-rescued SARS-CoV-2 was recovered from the lungs and brains of infected K18-hACE2 mice, and infection resulted in viral pneumonia with considerable changes in lung pathology, as seen previously with natural SARS-CoV-2 infection. In mice infected with RG-rescued SARS-CoV-2-mCherry, mCherry was detected in areas of lung consolidation and colocalized with clinically relevant SARS-CoV-2-assocated immunopathology. RG-rescued SARS-CoV-2 viruses successfully recapitulated many of the features of severe COVID-19 associated with the K18-hACE2 model of SARS-CoV-2 infection. With utility , the RG-rescued SARS-CoV-2 viruses will be valuable resources to advance numerous areas of SARS-CoV-2 basic research and COVID-19 vaccine development. To develop COVID-19 countermeasures, powerful research tools are essential. We produced a SARS-COV-2 reverse genetic (RG) infectious clone toolkit that will benefit a variety of investigations. In this study, we further prove the toolkit's value by demonstrating the utility of RG-rescued SARS-CoV-2 isolates. RG-rescued SARS-CoV-2 isolates reproduce disease signs and pathology characteristic of the K18-hACE2 mouse model of severe COVID-19 in infected mice. Having been validated as a model of severe COVID-19 previously using only natural SARS-CoV-2 isolated from patients, this is the first investigation of RG-rescued SARS-CoV-2 viruses in K18-hACE2 mice. The RG-rescued SARS-CoV-2 viruses will facilitate basic understanding of SARS-CoV-2 and the preclinical development of COVID-19 therapeutics.
新型严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）是正在发生的 2019 年冠状病毒病（COVID-19）大流行的病原体，它造成了广泛的死亡率和发病率，并破坏了社会经济结构。更好地了解 SARS-CoV-2 生物学并能够继续开发有效的对策的迫切需要，得益于生产有助于 SARS-CoV-2 研究的实验室工具。我们之前创建了一个直接可用的 SARS-CoV-2 工具包，其中包含 SARS-CoV-2 的用户友好型反向遗传（RG）感染性克隆。在这里，我们使用 K18-人血管紧张素转换酶 2（hACE2）小鼠，确认了 RG 拯救的 SARS-CoV-2 病毒能够重现已经在感染天然 SARS-CoV-2 分离株的小鼠中建立的感染谱、临床疾病和发病机制，这些分离株通常是从患者中获得的。感染 RG 拯救的 SARS-CoV-2 的 K18-hACE2 小鼠在感染后第 6 天出现严重的临床疾病和体重减轻。从感染 K18-hACE2 小鼠的肺部和大脑中回收了 RG 拯救的 SARS-CoV-2，感染导致病毒性肺炎，肺部病理学发生了很大变化，这与以前感染天然 SARS-CoV-2 时的情况相似。在感染 RG 拯救的 SARS-CoV-2-mCherry 的小鼠中，mCherry 检测到肺部实变区域，与临床上相关的 SARS-CoV-2 相关免疫病理学相关。RG 拯救的 SARS-CoV-2 病毒成功地再现了与 K18-hACE2 感染 SARS-CoV-2 模型相关的许多严重 COVID-19 的特征。由于其用途广泛，RG 拯救的 SARS-CoV-2 病毒将成为推进 SARS-CoV-2 基础研究和 COVID-19 疫苗开发的众多领域的宝贵资源。为了开发 COVID-19 对策，强大的研究工具是必不可少的。我们生产了一种 SARS-COV-2 反向遗传（RG）感染性克隆工具包，该工具包将有益于各种研究。在这项研究中，我们通过证明 RG 拯救的 SARS-CoV-2 分离株的用途，进一步证明了工具包的价值。RG 拯救的 SARS-CoV-2 分离株在感染小鼠中复制了与 K18-hACE2 小鼠严重 COVID-19 模型相关的疾病迹象和病理学特征。以前仅使用从患者中分离出的天然 SARS-CoV-2 对该模型进行了严重 COVID-19 的验证，这是首次在 K18-hACE2 小鼠中对 RG 拯救的 SARS-CoV-2 病毒进行研究。RG 拯救的 SARS-CoV-2 病毒将有助于深入了解 SARS-CoV-2 并促进 COVID-19 治疗的临床前开发。
