Neutralization activity of J.HAL® IgG candidates on VSV pseudotyped with SARS-CoV-2 UK variant spike (B1.1.7, Alpha) in A549-ACE2/TMPRSS2. (A and B) IgG candidates were tested for their ability to neutralize the entry of VSV pseudotyped with the spike of SARS-CoV-2 UK variant (B1.1.7, Alpha) in A549-ACE2/TMPRSS2 cells (A) M-3380 to M-3407 and (B) M-3379 to M-3398. For neutralization experiments, the pseudovirus was preincubated with two different concentrations of IgG candidates for 1 h at 37°C and the pseudovirus/antibody was subsequently added onto the cells and incubated for 20 h at 37°C. Infectivity was assessed at 20 h postinfection by luciferase assay. The results were normalized to a percentage of neutralization where the cell control (not-infected condition) and the virus control (nontreated, rVSV∆G-SARS-CoV-2-spike) are used to set 100% neutralization and 0% neutralization, respectively. Data were graphed as of % neutralization + SD using GraphPad prism software.