Correlation of vaccine-elicited antibody levels and neutralizing activities against SARS-CoV-2 and its variants

Liu, J.; Bodnar, B. H.; Wang, X.; Wang, P.; Meng, F.; Khan, A. I.; Saribas, A. S.; Padhiar, N. H.; McCluskey, E.; Shah, S.; Luo, J. J.; Hu, W.; Ho, W.-Z.

doi:10.1101/2021.05.31.445871

bioRxiv · 10.1101/2021.05.31.445871

Correlation of vaccine-elicited antibody levels and neutralizing activities against SARS-CoV-2 and its variants

Liu, J.·Bodnar, B. H.·Wang, X.·Wang, P.·Meng, F.·Khan, A. I.·Saribas, A. S.·Padhiar, N. H.·McCluskey, E.·Shah, S.·Luo, J. J.·Hu, W.·Ho, W.-Z.

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Abstract

Both Pfizer-BNT162b2 and Moderna-mRNA-1273 vaccines can elicit an effective immune response against SARS-CoV-2 infection. However, the elicited serum antibody levels vary substantially and longitudinally decrease after vaccination. We examined the correlation of vaccination-induced IgG levels and neutralization titers against newly emerged variants remains and demonstrate a significant reduction of neutralization activities against the variants (B.1.1.7, B.1.525, and B.1.351) in Pfizer or Moderna vaccined sera. There was a significant and positive correlation between serum IgG levels and ID50 titers for not only SARS-CoV-2 WT but also the variants. These findings indicate that a high level of anti-spike IgG may offer better protection against infection from SARS-CoV-2 and its variants. Therefore, it is necessary to longitudinally monitor specific serum IgG level for evaluating the protective efficacy of the vaccines against SARS-CoV-2 and its new variants.

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Liu, J., Bodnar, B. H., Wang, X., Wang, P., Meng, F., Khan, A. I., Saribas, A. S., Padhiar, N. H., McCluskey, E., Shah, S., Luo, J. J., Hu, W., Ho, W.-Z.. 2021-05-31. Correlation of vaccine-elicited antibody levels and neutralizing activities against SARS-CoV-2 and its variants. https://doi.org/10.1101/2021.05.31.445871

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