Associated virus-bacterial vaccine based on seasonal LAIV and S. pneumoniae chimeric peptide provide protection against post-influenza pneumococcal infection in mouse model

ABSTRACT

Severe influenza complications are often caused by Streptococcus pneumoniae infection, which presents the most common cause of community-acquired pneumonia. We evaluated in a mouse model an associated virus-bacterial vaccine based on seasonal live influenza vaccines (LAIV) and S. pneumoniae chimeric protein comprising flagellin (PSPF). Intranasal immunization of mice with a complex of trivalent LAIV and PSPF caused an increased release of early cytokines in the lungs of mice. The immunogenicity of LAIV and PSPF in the associated vaccine composition was sometimes decreased compared to each vaccine preparation alone. Nevertheless, only vaccination of mice with LAIV+PSPF significantly reduced lethality and the bacterial load in the lungs in a model of post-influenza bacterial pneumonia. The study of the interactions of influenza viruses with bacterial peptides is important during the development of associated virus-bacterial vaccines intended for the prevention of severe post-influenza bacterial complications.

KEYWORDS:

• Streptococcus pneumoniae
• influenza infection
• mucosal vaccine
• early cytokines

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contributions

Conceptualization, Y.D. and A.S.; methodology, G.L., T.K., I.L., A.R. and N.P.; formal analysis, I.L.; investigation, I.L., A.R. and N.P; writing – original draft preparation, Y.D.; writing – review and editing, Y.D., G.L. and A.S.; visualization, I.L.; supervision, A.S. All authors have read and agreed to the published version of the manuscript.

Data availability statement

The data supporting the findings obtained in this study are available in “Figshare” at http://doi.org/[10.6084/m9.figshare.16974706].

Additional information

Funding

Ministry of Science and Higher Education of the Russian Federation No. (075-15-2020-902), the Federal State Budgetary Scientific Institution—Institute of Experimental Medicine (FSBSI IEM) and the Scientific and Educational Center’s “Molecular Bases of Interaction of Microorganisms and Humans” of the world-class research center, the Center for Personalized Medicine at FSBSI IEM.