Extended Data Fig. 1: Binding properties of P2G3 and other anti-SARS-CoV-2 antibodies for recombinant Spike trimer proteins from 2019-nCoV and variants of concern in direct binding and Spike−ACE2 interaction assays.
a) Spike binding curves (n = 2) and b) Competitive binding studies between antibodies binding to the 2019-nCoV Spike RBD protein. RBD coupled beads pre-incubated with saturating concentrations of competitor antibody were used for binding studies with mAbs or ACE2. Competitors induced either strong blocking (Red boxes), partial competition (orange boxes) or non-competitive (white boxes) binding with the corresponding mAb to RBD. Red and yellow-hashed lines indicate incomplete blocking of the Spike-ACE2 interaction with Alpha, Gamma and Omicron Spike variant proteins (n = 2 for each mAb curve and Spike proteins). c) Spike-ACE2 blocking activity of a panel of in-house, authorized and clinically advanced anti-Spike mAbs and d) heatmap showing IC50, IC80 and Imax values for our panel of mAbs in the Spike-ACE2 assay. These Luminex based assays were performed with beads coupled with Spike trimer proteins from the original 2019-nCoV, D614G mutant, Alpha, Beta, Gamma, and Omicron SARS-CoV-2 variants of concern. Sotrovimab was included as a control mAb that binds the RBD without blocking the Spike-ACE2 interaction. e) Representative data for Spike-ACE2 blocking activity and Spike binding for P2G3 and P5C3 mAbs using the same Omicron BA.2 Spike trimer coated Luminex beads. Replicates shown for P2G3 and P5C3 are n = 8 and 7 in Spike-ACE2 assay and n = 4 and 2 in the Spike binding assay, respectively. Mean values ± SEM are shown.
