| |
Increased Potency and Breadth of SARS-CoV-2
Neutralizing Antibodies After a Third mRNA Vaccine Dose
|
| |
| |
bioRxiv posts many COVID19-related papers. A reminder: they have not been formally peer-reviewed and should not guide health-related behavior or be reported in the press as conclusive.
Increased Potency and Breadth of SARS-CoV-2 Neutralizing Antibodies After a Third mRNA Vaccine Dose
Frauke Muecksch, Zijun Wang, Alice Cho, Christian Gaebler, Tarek Ben Tanfous, Justin DaSilva, Eva Bednarski, Victor Ramos, Shuai Zong, Brianna Johnson, Raphael Raspe, Dennis Schaefer-Babajew, Irina Shimeliovich, Mridushi Daga, Kai-Hui Yao, Fabian Schmidt, Katrina G. Millard, Martina Turroja, Mila Jankovic, Thiago Y. Oliveria, Anna Gazumyan, Marina Caskey, Theodora Hatziioannou, Paul D. Bieniasz, Michel C. Nussenzweig
https://www.biorxiv.org/content/10.1101/2022.02.14.480394v1
Abstract
The omicron variant of SARS-CoV-2 infected very large numbers of SARS-CoV-2 vaccinated and convalescent individuals1-3. The penetrance of this variant in the antigen experienced human population can be explained in part by the relatively low levels of plasma neutralizing activity against Omicron in people who were infected or vaccinated with the original Wuhan-Hu-1 strain4-7. The 3rd mRNA vaccine dose produces an initial increase in circulating anti-Omicron neutralizing antibodies, but titers remain 10-20-fold lower than against Wuhan-Hu-1 and are, in many cases, insufficient to prevent infection7. Despite the reduced protection from infection, individuals that received 3 doses of an mRNA vaccine were highly protected from the more serious consequences of infection8. Here we examine the memory B cell repertoire in a longitudinal cohort of individuals receiving 3 mRNA vaccine doses 9,10. We find that the 3rd dose is accompanied by an increase in, and evolution of, anti-receptor binding domain specific memory B cells. The increase is due to expansion of memory B cell clones that were present after the 2nd vaccine dose as well as the emergence of new clones. The antibodies encoded by these cells showed significantly increased potency and breadth when compared to antibodies obtained after the 2nd vaccine dose. Notably, the increase in potency was especially evident among newly developing clones of memory cells that differed from the persisting clones in targeting more conserved regions of the RBD. Overall, more than 50% of the analyzed neutralizing antibodies in the memory compartment obtained from individuals receiving a 3rdmRNA vaccine dose neutralized Omicron. Thus, individuals receiving 3 doses of an mRNA vaccine encoding Wuhan-Hu-1, have a diverse memory B cell repertoire that can respond rapidly and produce antibodies capable of clearing even diversified variants such as Omicron. These data help explain why a 3rd dose of an mRNA vaccine that was not specifically designed to protect against variants is effective against variant-induced serious disease.
|
|
| |
| |
|
|
|
