Measuring Neutralizing Antibodies to SARS-CoV-2 Using Lentiviral Spike-Pseudoviruses.

Assays measuring neutralizing antibodies (nAbs) against SARS-CoV-2 are used to evaluate serological responses after SARS-CoV-2 infection and the potency of therapeutic antibodies and preventive vaccines. It is therefore imperative that neutralization assays be sensitive, specific, quantitative, and scalable for high throughput. Pseudoviruses are excellent surrogates for highly pathogenic viruses such as SARS-CoV-2 because they can be safely used to measure nAbs in a biosafety level-2 laboratory. In addition, pseudoviruses allow for easy introduction of mutations to study the effect of amino acid changes in the spike protein. In this chapter, we describe a recently optimized assay for measuring neutralizing antibodies to SARS-CoV-2 that uses a HIV-based lentiviral vector pseudotyped with the spike glycoprotein of SARS-CoV-2 to infect 293T cells stably expressing ACE2 and TMPRSS2.