Neutralizing activities of antibodies were assessed in a pseudovirus neutralization assay as described [42 (link)]. Briefly, 1 × 104 Vero cells were seeded per well of a 96‐flat bottom plate 1 day before the infection. Antibodies were pre‐diluted in cell culture medium and pre‐incubated for 30 min with vesicular stomatitis virus‐based pseudoviruses bearing the SARS‐CoV‐2 spike protein in a final volume of 100 μl per replicate (four replicates per experiment) before being inoculated on Vero cells. Pseudoviruses incubated in culture medium without antibody served as control (100% cell entry). At 16–18h postinoculation, the culture medium was aspirated and pseudovirus cell entry was analyzed by measuring the activity of virus‐encoded firefly luciferase in cell lysates using a commercial substrate (Beetle‐Juice, PJK GmbH) and a Hidex Sense plate luminometer (Hidex). IC50 values were calculated by plotting the virus entry in percent against the antibody concentrations and using the normalized response vs. inhibitor equation (variable slope) of GraphPad Prism 7.02.