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. 2022 Apr 21;78:103944. doi: 10.1016/j.ebiom.2022.103944

Figure 1.

Fig 1

Decreased neutralization of Omicron spike protein-pseudotyped viruses by convalescent sera, mRNA vaccine-elicited antibodies.

D614G, Beta, Delta and Omicron spike protein-pseudotyped viruses expressing dual GFP/nanoluciferase reporter genes with codon-optimized spike proteins deleted for the carboxy-terminal 19 amino acids were prepared as previously described.19 Equivalent amounts of virus were mixed with a 2-fold serial dilution of donor serum and then applied to ACE2.293T cells. Luciferase activity was measured two days post-infection. Each serum dilution was measured in triplicate and the experiment was done twice with similar results and IC50 was determined. Statistical significance was calculated by two-sided testing. (*P ≤ 0.05, **P ≤ 0.01, ***P ≤ 0.001, ****P ≤ 0.0001).

a. Neutralizing antibody titres of sera from study participants who had recovered from infection prior to the appearance of the current VOCs was measured against viruses pseudotyped by current VOCs (n = 10). IC50 of each donor serum is shown with the Geometric mean titre (GMT) for each group shown above the bar.

b. Neutralization of variant spike protein pseudotyped viruses by the sera of study participants fully vaccinated (two immunizations) with Pfizer BNT162b2 (n = 9) and Moderna mRNA-1273 mRNA vaccines (n = 8).

c. Neutralizing antibody titres of study participants without or with a previous history of SARS-CoV-2 infection were measured on the pseudotyped viruses. Sera were collected from study participants pre-vaccination, 1-month post-second vaccination with Pfizer BNT162b2, 7, 8 months post-second vaccination, and 1-month post-boost. Study participants were without previous SARS-CoV-2 infection (naïve) (left) (n = 12) or previously infected (experienced) (right) (n = 7). COVID-19 history was determined by symptoms and a PCR+ test or serology. GMTs for each group are shown above the bar.

d. Sequential neutralizing antibody titres of sera from individual study participants without or with previous history of SARS-CoV-2 infection is shown for each of the study participants shown above in C. GMTs are shown above.