Activity of neutralizing antibodies in sera during recovery from infection of humans with SARS-CoV-2 and variants of concern

DuPont, L., Snell, LB, Graham, C., et al. Neutralizing antibody activity in convalescent sera from human infections with SARS-CoV-2 and mutant strains of concern. NAT Microbiol 6, 1433-1442 (2021). https://doi.org/10.1038/s41564-021-00974-0

Commentary

This study provides unique insight into the longevity and cross-neutralizing activity of antibodies elicited by a presumptive vaccine candidate, the mutant spike protein, in analysis of convalescent sera.

Using sera from 38 individuals infected with Wave 1, we show that although serum potency was low against B.1.1.7 (alpha) and B1.351 (beta), we were able to detect cross-neutralizing activity up to 305 days after the onset of symptoms.

Over time, the difference in serum neutralizing potency against the SARS-CoV-2 alpha and beta mutants decreased, although the overall neutralizing activity decreased. Suggesting that continued antibody maturation increases resistance to spike mutations, the cross-neutralizing activity of Wave 1 sera was compared to sera from individuals infected with Alpha, Beta, and B.1.617.2 (Delta) variants up to 79 days after the onset of symptoms.

These sera neutralize infecting VOCs and the parent virus to similar levels, but cross-neutralization of different SARS-CoV-2VOC strains is reduced.

These findings will inform the optimization of vaccines to protect against SARS-CoV-2 variants.