AUTHOR=Vatzia Eleni , Allen Elizabeth R. , Manjegowda Tanuja , Morris Susan , McNee Adam , Martini Veronica , Kaliath Reshma , Ulaszewska Marta , Boyd Amy , Paudyal Basudev , Carr Veronica B. , Chrun Tiphany , Maze Emmanuel , MacLoughlin Ronan , van Diemen Pauline M. , Everett Helen E. , Lambe Teresa , Gilbert Sarah C. , Tchilian Elma TITLE=Respiratory and Intramuscular Immunization With ChAdOx2-NPM1-NA Induces Distinct Immune Responses in H1N1pdm09 Pre-Exposed Pigs JOURNAL=Frontiers in Immunology VOLUME=12 YEAR=2021 URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2021.763912 DOI=10.3389/fimmu.2021.763912 ISSN=1664-3224 ABSTRACT=

There is a critical need to develop superior influenza vaccines that provide broader protection. Influenza vaccines are traditionally tested in naive animals, although humans are exposed to influenza in the first years of their lives, but the impact of prior influenza exposure on vaccine immune responses has not been well studied. Pigs are an important natural host for influenza, are a source of pandemic viruses, and are an excellent model for human influenza. Here, we investigated the immunogenicity of the ChAdOx2 viral vectored vaccine, expressing influenza nucleoprotein, matrix protein 1, and neuraminidase in H1N1pdm09 pre-exposed pigs. We evaluated the importance of the route of administration by comparing intranasal, aerosol, and intramuscular immunizations. Aerosol delivery boosted the local lung T-cell and antibody responses, while intramuscular immunization boosted peripheral blood immunity. These results will inform how best to deliver vaccines in order to harness optimal protective immunity.