Abstract
Background: SARS-CoV-2 Omicron variant of concern (VOC) has evolved multiple mutations within the spike protein, raising concerns of increased antibody evasion. In this study, we assessed the neutralization potential of COVID-19 convalescent sera and sera from vaccinated individuals against ancestral SARS-CoV-2 and VOCs. Methods: The neutralizing activity of sera from 65 coronavirus disease (COVID-19) vaccine recipients and convalescent individuals against clinical isolates of ancestral SARS-CoV-2 and Beta, Delta, and Omicron VOCs was assessed using a micro-neutralization assay. Findings: Convalescent sera from unvaccinated individuals infected by the ancestral virus demonstrated reduced neutralization against Beta and Omicron VOCs. Sera from individuals that received three doses of the Pfizer or Moderna vaccines demonstrated reduced neutralization of the Omicron variant relative to ancestral SARS-CoV-2. Sera from individuals that were naturally infected with ancestral SARS-CoV-2 and subsequently received two doses of the Pfizer vaccine induced significantly higher neutralizing antibody levels against ancestral virus and all VOCs. Infection alone, either with ancestral SARS-CoV-2 or the Delta variant, was not sufficient to induce high neutralizing antibody titers against Omicron. Conclusions: In summary, we demonstrate that convalescent and vaccinated sera display varying levels of SARS-CoV-2 VOC neutralization. Data from this study will inform booster vaccination strategies against SARS-CoV-2 VOCs. Funding: This research was funded by the Canadian Institutes of Health Research (CIHR). VIDO receives operational funding from the Government of Saskatchewan through Innovation Saskatchewan and the Ministry of Agriculture and from the Canada Foundation for Innovation through the Major Science Initiatives for its CL3 facility.
| Original language | English |
|---|---|
| Pages (from-to) | 422-432.e3 |
| Journal | Med |
| Volume | 3 |
| Issue number | 6 |
| DOIs | |
| Publication status | Published - Jun 10 2022 |
Bibliographical note
Funding Information:SARS-CoV-2 research is supported in the laboratory of D.F. by the Canadian Institutes of Health Research (CIHR; OV5-170349 , VRI-173022 and VS1-175531 ). Research in the laboratory of A.B. is funded by CIHR , Saskatchewan Health Research Foundation (SHRF) and Lung Saskatchewan. Studies from which clinical samples were collected were funded by CIHR grants to A.J.M. and S.M. (# 439999 , # 465038 ); from the Canadian COVID-19 Immunity Task Force to S.E.S. and A.J.M.; and from the Toronto COVID Action Initiative Fund from the University of Toronto to J.L.W. and T.M. A.B., A-.C.G., J.L.W., S.M., and D.F. are members of the CIHR-funded Coronavirus Variants Rapid Response Network (CoVaRR-Net). R.K. is supported by an Ontario Together grant. We acknowledge contributions by Dr. Andrew G. McArthur who connected our teams to facilitate virus sequencing. We acknowledge the help of Dr. Akarin Asavajaru who handled shipping and receiving of samples.
Funding Information:
SARS-CoV-2 research is supported in the laboratory of D.F. by the Canadian Institutes of Health Research (CIHR; OV5-170349, VRI-173022 and VS1-175531). Research in the laboratory of A.B. is funded by CIHR, Saskatchewan Health Research Foundation (SHRF) and Lung Saskatchewan. Studies from which clinical samples were collected were funded by CIHR grants to A.J.M. and S.M. (#439999, #465038); from the Canadian COVID-19 Immunity Task Force to S.E.S. and A.J.M.; and from the Toronto COVID Action Initiative Fund from the University of Toronto to J.L.W. and T.M. A.B. A-.C.G. J.L.W. S.M. and D.F. are members of the CIHR-funded Coronavirus Variants Rapid Response Network (CoVaRR-Net). R.K. is supported by an Ontario Together grant. We acknowledge contributions by Dr. Andrew G. McArthur who connected our teams to facilitate virus sequencing. We acknowledge the help of Dr. Akarin Asavajaru who handled shipping and receiving of samples. Conceptualization, A.B. F.M. S.M. and D.F.; sample collection and selection: S.E.S. L.G. A.X.L. M.M. S.W. and A.C.G; methodology, A.B. J.L. A.K. K.B. P.A. F.M. and D.F.; formal analysis, A.B. J.L. A.K. F.M. and D.F.; reagents, J.L. K.N. R.K. R.M. A.L. S.E.S. L.G. A.X.L. M.M. S.W. A.-C.G. J.L.W. T.M. K.C. A.J.M. and S.M.; unrestricted access to all data, A.B. J.L. A.K. and D.F.; funding acquisition, A.B. and D.F.; writing – reviewing and editing, A.B. J.L. A.K. F.M. V.G. S.M. and D.F.; all authors read and approved the final manuscript and take responsibility for its content; supervision, A.B. and D.F. S.W. has served on advisory boards, speaking engagements, attended meetings and symposiums, and conducted clinical studies for ViiV Health Care, GSK, Merck, Janssen, and Gilead Sciences outside of the submitted work. A.J.M. reports income from advisory board membership from Astra-Zeneca, GlaxoSmithKline, Janssen, Medicago, Merck, Moderna, Pfizer, and Sanofi-Pasteur, and research grant funds paid to her institution from Pfizer and Sanofi-Pasteur.
Funding Information:
S.W. has served on advisory boards, speaking engagements, attended meetings and symposiums, and conducted clinical studies for ViiV Health Care, GSK, Merck, Janssen, and Gilead Sciences outside of the submitted work. A.J.M. reports income from advisory board membership from Astra-Zeneca, GlaxoSmithKline, Janssen, Medicago, Merck, Moderna, Pfizer, and Sanofi-Pasteur, and research grant funds paid to her institution from Pfizer and Sanofi-Pasteur.
Publisher Copyright:
© 2022 The Author(s)
ASJC Scopus Subject Areas
- General Medicine
PubMed: MeSH publication types
- Journal Article
- Research Support, Non-U.S. Gov't
