Development of pseudotyped VSV-SARS-CoV-2 spike variants for the assessment of neutralizing antibodies.

Serological studies with pseudotyped viruses offer a safer alternative to live SARS-CoV-2 in evaluating neutralizing antibodies, enabling research in standard labs. The SARS-CoV-2 Spike pseudotyped vesicular stomatitis virus (VSV) pseudoviruses were generated using Spike of Wuhan strain and two variants (B.1.1.7, B.1.351) and utilized to evaluate the serum neutralizing activity of human plasma samples of vaccinated (n = 13) and healthy people (n = 2) compared with a plaque assay with authentic virus. Neutralizing titer of convalescent plasma resulted with a good correlation (R = 0.7). We evaluated a safe and reliable pseudotyped virus system that effectively mimics authentic virus and correlates well with traditional assays. The developed system allows easier testing of variants and has the potential to improve vaccine development.