Abstract

Chile was one of the world leaders in the uptake of COVID-19 vaccination, and therefore, the characterization of neutralizing antibody (NAb) responses is critical for the understanding of the outcome of the COVID-19 pandemic at the local level. The requirement of classical neutralization assays to use infectious viruses in BSL-3 facilities, together with the lack of massive access to such an infrastructure in our region, led us to develop a fully characterized HIV-based SARS-CoV-2 pseudotype, which was used in a 96-well plate format to investigate NAb responses in clinical samples from individuals exposed to SARS-CoV-2, vaccinated or treated with convalescent plasma, as well as in the screening of SARS-CoV-2 entry inhibitors. This system represents an invaluable tool for countries lacking access to BSL-3 facilities, to characterize the humoral immunity against SARS-CoV-2 and other emerging viral pathogens.