A Subunit-based Influenza/SARS-CoV-2 Omicron Combined Vaccine
Induced Potent Protective Immunity in BALB/c Mice
Naru Zhang1,#, Zihui Ye1,#, Cun
Li2,#, Jie Zhou3,#, Wei
Xue2, Luying Xiang1, Yuewen
Chen1, Shuchang Chen1, Rouhan
Ye1, Jingyin Dong1, Jie
Zhou2,*, Shibo Jiang3,*, Haijun
Han1,*
1 School of Medicine, Hangzhou City University,
Hangzhou 310015, China
2 Department of Microbiology, Li Ka Shing Faculty of
Medicine, The University of Hong Kong, Hong Kong, China
3 Key Laboratory of Medical Molecular Virology
(MOE/NHC/CAMS), Shanghai Frontiers Science Center of Pathogenic Microbes
and Infection, School of Basic Medical Sciences, Shanghai Institute of
Infectious Disease and Biosecurity, Fudan University, Shanghai 200032,
China
*Correspondence: Jiezhou@hku.hk(J.Z.);shibojiang@fudan.edu.cn(S.J.); hanhj@hzcu.edu.cn (H.H.)
Abstract: Infection with influenza A virus (IAV) and severe
acute respiratory syndrome coronavirus 2 (SARS-CoV-2) poses a
significant risk to human life, health, and the global economy.
Vaccination is one of the most effective strategies in the fight against
infectious viruses. In this
study, we, for the first time, have evaluated the immunogenicity and
protective effect of an influenza/SARS-CoV-2 Omicron subunit combined
vaccine adjuvanted with MF59 and administered to BALB/c mice. Results
showed that the combined vaccine induced high levels of IgG,
IgG1, and IgG2a antibodies, as well as
influenza A H1N1/California/2009 virus-specific
hemagglutination-inhibiting antibodies in BALB/c mice. Moreover, this
subunit combined vaccine induced high titers of neutralization
antibodies against SARS-CoV-2 Omicron BA.5 pseudovirus and effectively
reduced the viral load of authentic SARS-CoV-2 Omicron BA.5.2 variant in
the cell culture supernatants. These results suggested that this subunit
combined vaccine achieved protective effect against both H1N1
A/California/07/2009 strain and SARS-CoV-2 Omicron BA.5.2 variant. It is
therefore expected that this study will establish the scientific
foundation for the next-step development of combined vaccines against
other strains or variants of IAV and SARS-CoV-2.
Keywords: Influenza A virus; SARS-CoV-2; Omicron BA.5; MF59;
subunit vaccines