Intranasal Immunization with Pressure Inactivated Avian Influenza Elicits Cellular and Humoral Responses in Mice

PLoS One. 2015 Jun 9;10(6):e0128785. doi: 10.1371/journal.pone.0128785. eCollection 2015.

Abstract

Influenza viruses pose a serious global health threat, particularly in light of newly emerging strains, such as the avian influenza H5N1 and H7N9 viruses. Vaccination remains the primary method for preventing acquiring influenza or for avoiding developing serious complications related to the disease. Vaccinations based on inactivated split virus vaccines or on chemically inactivated whole virus have some important drawbacks, including changes in the immunogenic properties of the virus. To induce a greater mucosal immune response, intranasally administered vaccines are highly desired as they not only prevent disease but can also block the infection at its primary site. To avoid these drawbacks, hydrostatic pressure has been used as a potential method for viral inactivation and vaccine production. In this study, we show that hydrostatic pressure inactivates the avian influenza A H3N8 virus, while still maintaining hemagglutinin and neuraminidase functionalities. Challenged vaccinated animals showed no disease signs (ruffled fur, lethargy, weight loss, and huddling). Similarly, these animals showed less Evans Blue dye leakage and lower cell counts in their bronchoalveolar lavage fluid compared with the challenged non-vaccinated group. We found that the whole inactivated particles were capable of generating a neutralizing antibody response in serum, and IgA was also found in nasal mucosa and feces. After the vaccination and challenge we observed Th1/Th2 cytokine secretion with a prevalence of IFN-γ. Our data indicate that the animals present a satisfactory immune response after vaccination and are protected against infection. Our results may pave the way for the development of a novel pressure-based vaccine against influenza virus.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Intranasal / adverse effects
  • Administration, Intranasal / methods*
  • Animals
  • Cytokines / genetics
  • Cytokines / metabolism
  • Dogs
  • Female
  • Influenza A Virus, H3N8 Subtype / immunology
  • Madin Darby Canine Kidney Cells
  • Mice
  • Mice, Inbred BALB C
  • Orthomyxoviridae Infections / immunology
  • Orthomyxoviridae Infections / prevention & control*
  • Pressure
  • Th1 Cells / immunology
  • Th2 Cells / immunology
  • Vaccines, Inactivated / administration & dosage
  • Vaccines, Inactivated / adverse effects
  • Vaccines, Inactivated / immunology*

Substances

  • Cytokines
  • Vaccines, Inactivated

Grants and funding

This work was supported by grants from Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ), Instituto Milênio de Biologia Estrutural em Biomedicina e Biotecnologia (IMBEBB), Instituto Nacional de Ciência e Tecnologia de Biologia Estrutural e Bioimagem (INBEB), and Programa de Apoio a Núcleos de Excelência (PRONEX) to J.L.S., A.M.O.G., and A.C.O. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.