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Clinical severe acute respiratory syndrome coronavirus 2 isolation and antiviral testing
Gregory Mathez1, Valeria Cagno1
1Institute of Microbiology, Lausanne University Hospital, 419236University of Lausanne, Switzerland.
Abstract:
Severe acute respiratory syndrome coronavirus 2 is an RNA virus currently causing a pandemic. Due to errors during replication, mutations can occur and result in cell adaptation by the virus or in the rise of new variants. This can change the attachment receptors' usage, result in different morphology of plaques, and can affect as well antiviral development. Indeed, a molecule can be active on laboratory strains but not necessarily on circulating strains or be effective only against some viral variants. Experiments with clinical samples with limited cell adaptation should be performed to confirm the efficiency of drugs of interest. In this protocol, we present a method to culture severe acute respiratory syndrome coronavirus 2 from nasopharyngeal swabs, obtain a high viral titer while limiting cell adaptation, and assess antiviral efficiency.
Insights
This study presents a method for culturing SARS-CoV-2 from patient swabs, achieving high viral titers with minimal adaptation. This approach aids in accurately assessing antiviral drug effectiveness against circulating viral strains and emerging variants.
Area of Science:
- Virology
- Infectious Diseases
- Drug Discovery
Background:
- Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mutations lead to viral adaptation and new variants.
- Viral variants can alter receptor usage, plaque morphology, and antiviral susceptibility.
- Antivirals effective against lab strains may not work against circulating or variant strains.
Purpose of the Study:
- To present a protocol for culturing SARS-CoV-2 from nasopharyngeal swabs.
- To achieve high viral titers while minimizing in vitro cell adaptation.
- To enable reliable assessment of antiviral efficiency against clinical SARS-CoV-2 isolates.
Main Methods:
- Culture of SARS-CoV-2 from clinical nasopharyngeal swabs.
- Optimization of culture conditions to maximize viral titer.
- Minimization of cell adaptation during viral culture.
- Antiviral drug screening using cultured clinical isolates.
Main Results:
- Successful isolation and high-titer culture of SARS-CoV-2 from clinical samples.
- Demonstration of a method to limit viral cell adaptation during culture.
- Establishment of a platform for assessing antiviral activity against relevant viral strains.
Conclusions:
- The presented protocol facilitates the culture of SARS-CoV-2 from patient samples with limited adaptation.
- This method is crucial for validating antiviral efficacy against clinically relevant viral strains and variants.
- Accurate assessment of antiviral drugs requires testing against minimally adapted clinical isolates.
