The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus, which is highly pathogenic and classified as a biosafety level 3 (BSL-3) agent, has greatly threatened global health and efficacious antivirals are urgently needed. The high requirement of facilities to manipulate the live virus has limited the development of antiviral study. Here, we constructed a reporter replicon of SARS-CoV-2, which can be handled in a BSL-2 laboratory. The Renilla luciferase activity effectively reflected the transcription and replication levels of the replicon genome. We identified the suitability of the replicon in antiviral screening using the known inhibitors, and thus established the replicon-based high-throughput screening (HTS) assay for SARS-CoV-2. The application of the HTS assay was further validated using a few hit natural compounds, which were screened out in a SARS-CoV-2 induced cytopathic-effect-based HTS assay in our previous study. This replicon-based HTS assay will be a safe platform for SARS-CoV-2 antiviral screening in a BSL-2 laboratory without the live virus.

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SARS-CoV-2复制子，用于高通量抗病毒筛选

严重的急性呼吸综合症冠状病毒2（SARS-CoV-2）病毒具有高致病性，被列为生物安全3级（BSL-3）药剂，已严重威胁全球健康，迫切需要有效的抗病毒药。处理活病毒的设施的高要求限制了抗病毒研究的发展。在这里，我们构建了SARS-CoV-2的报告复制子，可以在BSL-2实验室中进行处理。海肾荧光素酶活性有效地反映了复制子基因组的转录和复制水平。我们使用已知的抑制剂确定了复制子在抗病毒筛选中的适用性，从而建立了针对SARS-CoV-2的基于复制子的高通量筛选（HTS）分析。使用一些热门天然化合物进一步验证了HTS分析的应用，在我们先前的研究中，是在SARS-CoV-2诱导的基于细胞病变效应的HTS分析中筛选出的。这种基于复制子的HTS分析将成为在没有活病毒的BSL-2实验室中筛选SARS-CoV-2抗病毒药物的安全平台。