Extended Data Fig. 6: Expression and antigen-binding ability of CVRs targeting distinct SARS-CoV-2 neutralizing epitopes.
a, Western blot analysis of the expression levels of indicated scFv-CVRs transiently expressed in HEK293T cells. Data are representative of two independent experiments. b, Binding of SARS-CoV-2 S-trimer to HEK293T cells expressing the indicated CVRs. Data are representative of three assays using independent preparations of proteins. c, Flow cytometry analysis of the binding efficiency of scFv-mFc with HEK293T cells transiently expressing the SARS-CoV-2 Spike proteins and ZsGreen simultaneously. The ZsGreen positive cells were gated for subsequent analysis of mFc binding efficiency. Data representative from a single experiment with mean values (n = 3 wells of biologically independent cells) indicated. d, Trypsin-mediated S2′ cleavage of SARS2-CoV-2 PSV in the presence of soluble receptors or CB6-scFv-mFc. The concentrated SARS-CoV-2 PSV particles were incubated with 100 μg ml−1 of soluble receptors or CB6-scFv-mFc for 1 h, followed by incubation with the indicated concentration of TPCK-treated trypsin for 30 min. Western blot analysis was conducted by detecting the S2P6 epitope in the S2 subunit. Data are representative of three independent assays with similar results.
