Figure 4.

Enhanced neutralization by dimer, homo-trimer, and IgM versions of R14 or S43

(A) The dimers were constructed via nanobody fusing with human IgG1 Fc, homo-trimers were constructed with three nanobodies by head-to-tail fusion, and the IgM versions (decameric constructs) were constructed via nanobody fusing to the Fc of IgM.

(B) Radar plot demonstrating the neutralization profile of antibodies to prototype and Delta and Omicron sub-variants. For the antibody with IC₅₀ of <100% inhibition at the highest tested concentration, 1/IC₅₀ is thought of as zero.

(C) IC₅₀ values of multivalent constructs of R14 and S43 against pSARS-CoV-2 prototype, Delta, and Omicron (BA.1, BA.2, BA.2.12.1, BA.2.75, BA.3, and BA.4/5) in Vero cells. IC₅₀ values for pseudotyped viruses are the mean ± SD of three independent results. Experiments were independently repeated three times with similar results, and one representative curve is displayed in the Figure S4. “∗” indicates that the antibody showed <100% inhibition at the highest tested concentration.

(D) IC₅₀ values for live viruses are the mean of two independent experiments.