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Influenza A Virus Studies in a Mouse Model of Infection
10:44

Influenza A Virus Studies in a Mouse Model of Infection

Published on: September 7, 2017

Pathogenicity of different PR8 influenza A virus variants in mice is determined by both viral and host factors

Paulina Blazejewska1, Lukasz Koscinski, Nuno Viegas

  • 1Department of Infection Genetics, Helmholtz Centre for Infection Research and University of Veterinary Medicine Hannover, Braunschweig, Germany.

Virology
|January 25, 2011
PubMed

Insights

Three mouse-adapted influenza A virus variants showed varied virulence in different mouse strains. The HA gene was identified as a key factor determining the virulence of the PR8F variant.

Area of Science:

  • Virology
  • Immunology
  • Genetics

Background:

  • Influenza A virus (IAV) poses a significant public health threat.
  • Understanding IAV virulence factors is crucial for developing effective vaccines and therapeutics.
  • Mouse models are essential for studying IAV pathogenesis and host responses.

Purpose of the Study:

  • To compare the virulence and replication rates of three mouse-adapted PR8 IAV variants.
  • To identify the genetic determinants of virulence for specific IAV variants.
  • To investigate the host-pathogen interactions influencing IAV pathogenicity.

Main Methods:

  • Comparative analysis of three PR8 IAV variants (PR8M, PR8F, hvPR8) in DBA/2J and C57BL/6J mice.
  • Assessment of viral load, pathogenicity, and host immune cell infiltration.
  • 3D-protein structure prediction of hemagglutinin (HA) to analyze cleavage site accessibility.
  • Re-assortment experiments to determine the role of the HA gene in virulence.

Main Results:

  • Significant differences in pathogenicity were observed between the PR8 variants and mouse strains.
  • PR8M variant was lethal in DBA/2J mice but not C57BL/6J mice.
  • PR8F and hvPR8 variants were lethal in both mouse strains, with PR8F showing higher viral loads and leukocyte infiltration.
  • HA gene alterations in PR8F were linked to increased HA cleavage site accessibility and were identified as the main determinant of its virulence.

Conclusions:

  • The virulence of PR8 IAV variants is highly dependent on both the virus strain and the host genetic background.
  • The HA gene plays a critical role in determining the virulence of the PR8F influenza A virus variant.
  • Understanding these genetic determinants can inform the development of strategies to control influenza outbreaks.

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