Pseudotyped virus neutralization assay
VIRUS
Serum samples inactivated for 30 minutes at 56°C were 3-fold serially diluted (from 1:5 to 1:10935) in supplemented DMEM with 10% FBS. Samples were incubated with 3 ng of p24 HIV-1-based SARS-CoV-2 variant pseudotyped virus D614G (B.1 lineage) or Omicron (BA.1 lineage)) during 1 h at 37°C, and 1 × 10