Abstract
Short title of the paper …
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the
causative agent of COVID-19. The development of antiviral drugs for
COVID-19 has been hampered by the requirement of a biosafety level 3
(BSL3) laboratory for experiments related to SARS-CoV-2, and by the lack
of easy and precise methods for quantification of infection. Here, we
developed a SARS-CoV-2 viral vector composed of all four SARS-CoV-2
structural proteins constitutively expressed in lentivirally transduced
cells, combined with an RNA replicon deleted for SARS-CoV-2 structural
protein genes S, M and E, and expressing a luciferase-GFP fusion
protein. We show that, after concentrating viral stocks by
ultracentrifugation, the SARS-CoV-2 viral vector is able to infect two
human cell lines expressing receptors ACE2 and TMPRSS2. Both luciferase
activity and GFP fluorescence were detected, and transduction was
remdesivir-sensitive. We also show that this vector is inhibited by
three type I interferons (IFN-I) subtypes. Although improvements are
needed to increase infectious titers, this vector system may prove
useful for antiviral drug screening and SARS-CoV-2-related
investigations.