Ultrastructural analysis of the late stages of SARS-CoV-2 infection in Vero cells

ABSTRACT

Since 2019, the world is experiencing a COVID-19 pandemic period caused by the new betacoronavirus SARS-CoV-2. This pathogen has led more than millions of people to death and many questions about the molecular mechanisms of interactions with the host cell are still unanswered. Viral entry and egress are important steps for the virus cycle. Although SARS-CoV-2 internalization has been largely studied, the egress steps of SARS-CoV-2 are still not fully described. In this study, we address the morphological characteristics of SARS-CoV-2 morphogenesis and egress by transmission and high-resolution scanning microscopy, with the aim of adding more information about the route of nascent virions towards the extracellular medium. Our results reinforce the role of small secretory vesicles as a vehicle to the individual egress, which could be the predominant via to the SARS-CoV-2 egress in Vero cells.