Fig. 1: Avidity enhances binding and neutralization of VHH against SARS-CoV-2.
From: Multivalency transforms SARS-CoV-2 antibodies into ultrapotent neutralizers
a Schematic representation of a monomeric VHH domain and its multimerization using a conventional Fc (dark red) scaffold or human apoferritin (gray). b Size exclusion chromatography and SDS-PAGE of apoferritin alone (gray) and VHH-72 apoferritin particles (gold). c Negative stain electron microscopy of VHH-72 apoferritin particles. (Scale bar 50 nm, representative of two independent experiments). d Comparison of the binding avidity (apparent KD) of VHH-72 to SARS-CoV-2 S protein when displayed in a bivalent (dark red) or 24-mer (gold) format. Bars indicate the mean values of n = 2 biologically independent experiments. Apparent KD lower than 10−12 M (dash line) is beyond the instrument detection limit. e Neutralization potency against SARS-CoV-2 PsV (color coding is as in (d)). One representative out of two biologically independent replicates with similar results is shown. Mean values ± SD of two technical replicates is represented in the plot. Median IC50 values of the two biologically independent replicates are shown. Source data are provided as a Source Data file.
