ABSTRACT
BACKGROUND INFORMATION: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection induces an alteration in the endomembrane system of the mammalian cells. In this study, we used transmission electron microscopy and electron tomography to investigate the main structural alterations in the cytoplasm of Vero cells infected with a SARS-CoV-2 isolate from São Paulo state (Brazil). RESULTS: Different membranous structures derived from the zippered endoplasmic reticulum were observed along with virus assembly through membrane budding. Also, we demonstrated the occurrence of annulate lamellae in the cytoplasm of infected cells and the presence of virus particles in the perinuclear space. CONCLUSIONS AND SIGNIFICANCE: This study contributes to a better understanding of the cell biology of SARS-CoV-2 and the mechanisms of the interaction of the virus with the host cell that promote morphological changes, recruitment of organelles and cell components, in a context of a virus-induced membrane remodelling.
Subject(s)
Endoplasmic Reticulum/virology , Intracellular Membranes/virology , Nuclear Envelope/virology , SARS-CoV-2 , Animals , COVID-19 , Chlorocebus aethiops , Electron Microscope Tomography , Endoplasmic Reticulum/ultrastructure , Humans , Intracellular Membranes/ultrastructure , Microscopy, Electron, Transmission , Nuclear Envelope/ultrastructure , SARS-CoV-2/growth & development , SARS-CoV-2/ultrastructure , Vero Cells , Virus Assembly , Virus ReplicationABSTRACT
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 h 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.