Broad neutralizing antibody response of a monomeric spike–based SARS-CoV-2 bivalent vaccine against diverse variants

S Siling Wang (State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University) H Hui Sun Y Yizhen Wang (State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University) Z Zikang Wang (State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University) L Lunzhi Yuan (State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University) H Huilin Guo (State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University) J Jiahua Gao (State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University) M Miaolin Lan (State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University) Y Yangtao Wu (State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University) H Huixian Shang (State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University) X Xiuting Chen (State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University) Z Zheng Chen J Jiayi Hu (State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University) Z Zimin Tang (State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University) G Guiping Wen (Department of Central Laboratory, Women and Children’s Hospital, School of Medicine, Xiamen University) D Dong Ying (State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University) C Chang Liu Y Yanan Jiang (State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University) J Jinfu Su (State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University) M Min Lin T Ting Wu (Children’s Hospital, Zhejiang University School of Medicine) S Shaowei Li (Department of Chemistry) T Tianying Zhang J Jun Zhang Y Yi Guan (State Key Laboratory of Emerging Infectious Diseases, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong) N Ningshao Xia (State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University) Q Quan Yuan Q Qingbing Zheng (State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University) Y Yali Zhang Z Zizheng Zheng (State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University)

Abstract

severeacute respiratory syndrome coronavirus 2 (SARS-CoV-2) bivalent vaccines show potential against variants but lack a full understanding of the immunological mechanisms that drive broadly neutralizing antibodies (bnAbs). This study explored the immunogenicity of a bivalent vaccine in rhesus macaques, containing spike (S) proteins from the prototype (S prototype ) and chimeric S protein (S 1628x ). The vaccine induced bnAbs against multiple variants, including challenging subvariants like EG.1, BA.2.86, and JN.1. The monomeric S protein exposed less accessible regions within the receptor-binding domain (RBD) “inner face” and “NTD face” and subdomains 1, eliciting a diverse array of bnAbs against various Omicron subvariants. Notably, antibodies targeting the conserved RBD inner face, such as 4A5, showed potent neutralization across all tested variants. Structural analyses provide insights into the broad protectiveness of these vaccine-elicited nAbs. This study underscores the potential of bivalent vaccines with monomeric spike proteins to confer broad-spectrum immunity, offering a promising direction for future SARS-CoV-2 universal vaccine design.

Article Details

Volume / Issue Vol. 122, Issue 35
Published September 02, 2025
ISSN 0027-8424
Publisher National Academy of Sciences

Authors (30)

S

Siling Wang

State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University

H

Hui Sun

Y

Yizhen Wang

State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University

Z

Zikang Wang

State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University

L

Lunzhi Yuan

State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University

H

Huilin Guo

State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University

J

Jiahua Gao

State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University

M

Miaolin Lan

State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University

Y

Yangtao Wu

State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University

H

Huixian Shang

State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University

X

Xiuting Chen

State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University

Z

Zheng Chen

J

Jiayi Hu

State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University

Z

Zimin Tang

State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University

G

Guiping Wen

Department of Central Laboratory, Women and Children’s Hospital, School of Medicine, Xiamen University

D

Dong Ying

State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University

C

Chang Liu

Y

Yanan Jiang

State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University

J

Jinfu Su

State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University

M

Min Lin

T

Ting Wu

Children’s Hospital, Zhejiang University School of Medicine

S

Shaowei Li

Department of Chemistry

T

Tianying Zhang

J

Jun Zhang

Y

Yi Guan

State Key Laboratory of Emerging Infectious Diseases, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong

N

Ningshao Xia

State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University

Q

Quan Yuan

Q

Qingbing Zheng

State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University

Y

Yali Zhang

Z

Zizheng Zheng

State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, School of Life Sciences, School of Public Health, Xiamen University