FIG 2.

Convalescent serum, antibodies elicited by BNT162b2 vaccine, antibodies elicited by mRNA-1273 vaccine, antibody REGN10933, and antibody REGN10987 all neutralize B.1.526 variant spikes. (A) Neutralization of viruses with D614G, B.1.526 variant spikes by convalescent-phase sera (n = 6). The data are shown as the percentage infectivity in the absence of serum (left). IC₅₀ (serum dilution) of sera from convalescent individuals (n = 6) against virus with B.1.526 and E484K variant spikes (right). (B) Neutralizing titers of serum samples from BNT162b2-vaccinated individuals (n = 5) (left) and mRNA-1273-vaccinated donors (n = 3) (right) were measured. IC₅₀ values of neutralization of virus with D614G, B.1.1.7, B.1.351, and B.1.526 are shown. (C) A 1:1 mixture of the two antibodies was measured on viruses pseudotyped with B.1.526, D614G and E484K variant spike proteins. Neutralization curves of REGN10933, REGN10987, and a 1:1 mixture of REGN10933 and REGN10987 on viruses with the B.1.526, D614G and E484K variant spike proteins. (D). The effect of the MAb ratio on neutralization of variant B.1.526 (E484K) was tested by holding REGN10933 constant at its IC₅₀ and titrating in REGN10987 (left) or holding REGN10987 constant at its IC₅₀ and titrating in REGN10933.