Intracellular flow cytometry complements RT-qPCR detection of circulating SARS-CoV-2 variants of concern
Emiel Vanhulle,
Becky Provinciael,
Joren Stroobants,
Anita Camps,
Piet Maes,
Kurt Vermeire
Affiliations
Emiel Vanhulle
1KU Leuven, Department of Microbiology, Immunology & Transplantation, Rega Institute, Laboratory of Virology & Chemotherapy, Herestraat 49, Leuven, 3000, Belgium
Becky Provinciael
1KU Leuven, Department of Microbiology, Immunology & Transplantation, Rega Institute, Laboratory of Virology & Chemotherapy, Herestraat 49, Leuven, 3000, Belgium
Joren Stroobants
1KU Leuven, Department of Microbiology, Immunology & Transplantation, Rega Institute, Laboratory of Virology & Chemotherapy, Herestraat 49, Leuven, 3000, Belgium
Anita Camps
1KU Leuven, Department of Microbiology, Immunology & Transplantation, Rega Institute, Laboratory of Virology & Chemotherapy, Herestraat 49, Leuven, 3000, Belgium
Piet Maes
2KU Leuven, Department of Microbiology, Immunology & Transplantation, Rega Institute, Laboratory of Clinical & Epidemiological Virology, Herestraat 49, Leuven, 3000, Belgium
Kurt Vermeire
1KU Leuven, Department of Microbiology, Immunology & Transplantation, Rega Institute, Laboratory of Virology & Chemotherapy, Herestraat 49, Leuven, 3000, Belgium
Basic and antiviral research on SARS-CoV-2 rely on cellular assays of virus replication in vitro. In addition, accurate detection of virus-infected cells and released virus particles is needed to study virus replication and to profile new candidate antiviral drugs. Here, by flow cytometry, we detect SARS-CoV-2 infection at single cell level and distinguish infected Vero E6 cells from uninfected bystander cells. Furthermore, based on the viral nucleocapsid expression, subpopulations of infected cells that are in an early or late phase of viral replication can be differentiated. Importantly, this flow cytometric technique complements our duplex RT-qPCR detection of viral E and N, and it can be applied to all current SARS-CoV-2 variants of concern, including the highly mutated Omicron variant.
