Cross-neutralizing activity of potent SARS-CoV-2 neutralizers. (A) Graphs showing the neutralization curves of SARS-CoV-2 and selected VOCs by potent anti-RBD IgG antibodies as determined with the S-Fuse neutralization assay. Error bars indicate the SD of duplicate values. IC₅₀ values are indicated in the top left-hand corner (in blue). ND, not determined. (B) Graphs showing the neutralization curves of SARS-CoV-2 and selected VOCs by Cv2.1169 and Cv2.3194 IgG antibodies as determined with the pseudo-neutralization assay. Error bars indicate the SD of duplicate values. IC₅₀ values are indicated in the top left-hand corner (in blue). (C) Amino acid alignment of the heavy chains (IgH, left) and light chains (IgL, right) of the V_H1-58–encoded human antibodies produced from SARS-CoV-2 spike–captured memory B-cell antibodies. Dendrograms showing the relationship between V_H1-58–encoded human antibodies generated from the IgH and IgL sequence alignments are shown at the bottom. (D) ELISA graphs showing the reactivity of V_H1-58–encoded antibodies against the SARS-CoV-2 tri-S protein. Means ± SD of duplicate values are shown. (E) ELISA graphs comparing the binding of Cv2.5179 and Cv2.1169 antibodies to RBD proteins. Means ± SD of duplicate values are shown. (F) Competition ELISA graphs showing the binding of biotinylated SARS-CoV-2 tri-S and RBD proteins to the immobilized soluble ACE2 ectodomain in presence of Cv2.5179 or Cv2.1169 antibody as a competitor. Means ± SD of duplicate values are shown. (G) Graphs showing the neutralization curves of SARS-CoV-2 and VOCs by Cv2.5179 IgG antibody as determined with the S-Fuse neutralization assay. Means ± SD of duplicate values are shown. IC₅₀ values are indicated in the top left-hand corner (in blue).