Visualization of SARS-CoV-2 infection dynamic

Ye, C.; Chiem, K.; Park, J.-G.; Silvas, J.; Morales Vasquez, D.; Torrelles, J. B.; Kobie, J.; Walter, M. R.; de la Torre, J. C.; Martinez-Sobrido, L.

doi:10.1101/2021.06.03.446942

bioRxiv · 10.1101/2021.06.03.446942

Visualization of SARS-CoV-2 infection dynamic

Ye, C.·Chiem, K.·Park, J.-G.·Silvas, J.·Morales Vasquez, D.·Torrelles, J. B.·Kobie, J.·Walter, M. R.·de la Torre, J. C.·Martinez-Sobrido, L.

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Abstract

Replication-competent recombinant viruses expressing reporter genes provide valuable tools to investigate viral infection. Low levels of reporter gene expressed from previous reporter-expressing rSARS-CoV-2 have jeopardized their use to monitor the dynamics of SARS-CoV-2 infection in vitro or in vivo. Here, we report an alternative strategy where reporter genes were placed upstream of the viral nucleocapsid gene followed by a 2A cleavage peptide. The higher levels of reporter expression using this strategy resulted in efficient visualization of rSARS-CoV-2 in infected cultured cells and K18 hACE2 transgenic mice. Importantly, real-time viral infection was readily tracked using a non-invasive in vivo imaging system and allowed us to rapidly identify antibodies which are able to neutralize SARS-CoV-2 infection in vivo. Notably, these reporter-expressing rSARS-CoV-2 retained wild-type virus like pathogenicity in vivo, supporting their use to investigate viral infection, dissemination, pathogenesis and therapeutic interventions for the treatment of SARS-CoV-2 in vivo.

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Ye, C., Chiem, K., Park, J.-G., Silvas, J., Morales Vasquez, D., Torrelles, J. B., Kobie, J., Walter, M. R., de la Torre, J. C., Martinez-Sobrido, L.. 2021-06-04. Visualization of SARS-CoV-2 infection dynamic. https://doi.org/10.1101/2021.06.03.446942

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