Fig. 5
The binding affinity between antibody escape mutants and ACE2. a Affinity measurement of purified RBD mutants for binding to immobilized ACE2-Fc by surface plasmon resonance (SPR). The Kon and Koff were determined by BIAcore and the KD were computed as Koff/Kon. Neutralization fold change was calculated as follows: KD value of RBD wildtype/KD value of RBD mutants. b The residues that are important for resistance to antibodies are presented on the interface of the ACE2 and RBD. The position of mutants that enhance ACE2 binding affinity are highlighted in red (affinity fold change ≥ 2.5); comparable to wildtype are in orange (affinity fold change between 2.5 and 0.4); reduce ACE2 binding affinity are in slate blue (affinity fold change ≤ 0.4). The data represent one representative experiment of two independent experiments