Significance The urgency of curbing the COVID-19 pandemic has motivated many investigators to pivot their research to understand the basic biology of SARS-CoV-2 and to search for new pharmaceutical compounds for potential COVID-19 treatment. However, most SARS-CoV-2 studies require biosafety level 3 facilities, which are in high demand, costly, and difficult to access. To overcome these limitations, we engineered a SARS-CoV-2 replicon, which is a modified virus subgenome capable of self-replicating without producing infectious virus, allowing the viral replication to be studied in a conventional biomedical laboratory setting. The replicon system also provides a valuable tool to screen and test antiviral compounds in biologically relevant cells. Successful implementation of the technology will accelerate the development of effective treatment for SARS-CoV-2 infection. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) research and antiviral discovery are hampered by the lack of a cell-based virus replication system that can be readily adopted without biosafety level 3 (BSL-3) restrictions. Here, the construction of a noninfectious SARS-CoV-2 reporter replicon and its application in deciphering viral replication mechanisms and evaluating SARS-CoV-2 inhibitors are presented. The replicon genome is replication competent but does not produce progeny virions. Its replication can be inhibited by RdRp mutations or by known SARS-CoV-2 antiviral compounds. Using this system, a high-throughput antiviral assay has also been developed. Significant differences in potencies of several SARS-CoV-2 inhibitors in different cell lines were observed, which highlight the challenges of discovering antivirals capable of inhibiting viral replication in vivo and the importance of testing compounds in multiple cell culture models. The generation of a SARS-CoV-2 replicon provides a powerful platform to expand the global research effort to combat COVID-19.
【저자키워드】 COVID-19, SARS-CoV-2, antivirals, replicon, high-throughput antiviral screening, 【초록키워드】 Treatment, severe acute respiratory syndrome coronavirus 2, coronavirus, Antiviral, SARS-COV-2 infection, COVID-19 pandemic, Genome, Antiviral compounds, severe acute respiratory syndrome Coronavirus, virus, Laboratory, Replication, Viral, cells, viral replication, Cell culture, implementation, Research, RdRP, virus replication, respiratory, in vivo, inhibitor, reporter, platform, mechanism, Infectious virus, cell lines, biosafety level, level 3, acute respiratory syndrome, acute respiratory syndrome coronavirus, significant differences, this system, RdRp mutations, Compound, effort, investigator, urgency, construction, cell line, inhibiting viral replication, progeny virions, limitations, Antiviral compound, effective, Biosafety Level 3, BSL-3, highlight, lack, inhibited, provide, overcome, adopted, costly, producing, accelerate, expand, competent, Significant, biology of SARS-CoV-2, RdRp mutation, Significance, 【제목키워드】 Antiviral, reporter, Generation,