Fig. 6

Design and experimental characterization of Tr67. a Schematic diagram illustrating the trimerization of Nb67 nanobody fused with the optimal trimerization unit 5ff (see its amino-acid sequence of the fusion monomer of Nb67 with 5ff in (Additional file 1: Table S1). b SEC and Native-PAGE analysis of Tr67, showing high trimerization tendency and conformational homogeneity. c BLI measurement of the binding kinetics of the monovalent Nb67 and Tr67 to the immobilized RBD of SARS-CoV-2 pseudovirus (Omicron BA.1). d Neutralizing activities of Nb67 and Tr67 against SARS-CoV-2 pseudovirus (Omicron BA.1). Three independent experiments were performed