Ultrastructural analysis of SARS-CoV-2 interactions with the host cell via high resolution scanning electron microscopy

ABSTRACT

SARS-CoV-2 is the cause of the ongoing COVID-19 pandemic. Here, we investigated the interaction of this new coronavirus with Vero cells using high resolution scanning electron microscopy. Surface morphology, the interior of infected cells and the distribution of viral particles in both environments were observed 2 and 48 hours after infection. We showed areas of viral processing, details of vacuole contents, and viral interactions with the cell surface. Intercellular connections were also approached, and viral particles were adhered to these extensions suggesting direct cell-to-cell transmission of SARS-CoV-2. HighlightsWe used high resolution scanning electron microscopy to investigate Vero cells infected with SARS-CoV-2 at 2 and 48 hours post-infection. The central conclusions of this work include O_LIInfected cells display polarization of their cytosol forming a restricted viroplasm-like zone dedicated to virus production and morphogenesis. C_LIO_LIThis is the first demonstration of SARS-CoV-2 attachment by scanning electron microscopy. C_LIO_LIThis is the first scanning electron microscopy images of the interior of SARS-CoV-2 infected cells and exploration of their vacuole contents. C_LIO_LIPerspective-viewing of bordering vesicles in close association with vacuoles. C_LIO_LIObservation of membrane ruffles and structures suggestive of exocytosis on the surface of infected cells. C_LIO_LIThe first demonstration of viral surfing in cell-to-cell communication on SARS-CoV-2 infection. C_LI