Correlation of SARS-CoV-2 Viral Neutralizing Antibody Titers with Anti-Spike Antibodies and ACE-2 Inhibition among Vaccinated Individuals
Brian Grunau, Martin A. Prusinkiewicz, Michael Asamoah-Boaheng, Liam Golding, Pascal M. Lavoie, Martin Petric, Paul N. Levett, Scott Haig, Vilte Barakauskas, Mohammad Ehsanul Karim, Agatha N. Jassem, Steven J. Drews, Sadaf Sediqi, David A. Goldfarb
Abstract
Live viral neutralizing antibody titers are an accepted measure of immunity; however, testing procedures are labor-intensive. COVID-19 antibody and angiotensin converting enzyme-2 (ACE-2) levels have been used as surrogates to live viral neutralizing antibody titers; however, validity among vaccinated individuals is unclear. Using samples from 120 two-dose mRNA vaccinees without previous COVID-19, we found that live viral neutralization was correlated with COVID-19 antibody and ACE2 binding levels. When grouping samples by the time interval between vaccination and sample blood collection, samples collected over 158 days after the first vaccine and over 71 days from the second vaccine demonstrated stronger correlation between live viral neutralization titers and both antibody and ACE2 levels, in comparison to those collected earlier.