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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

Recent H5N1 avian influenza A virus increases rapidly in virulence to mice after a single passage in mice

Masaji Mase1, Nobuhiko Tanimura1, Tadao Imada1

  • 1Department of Infectious Diseases, National Institute of Animal Health, 3-1-5 Kannondai, Tsukuba, Ibaraki 305-0856, Japan.

The Journal of General Virology
|November 14, 2006
PubMed

Insights

The H5N1 avian influenza virus gained high mouse lethality after a PB2 protein mutation. Recovered viruses showed increased pathogenicity, highlighting the need for monitoring viral evolution in mammals.

Area of Science:

  • Virology
  • Pathogen Evolution
  • Mammalian Pathogenicity

Background:

  • Avian influenza A virus (H5N1) poses a potential threat to mammals.
  • Understanding viral adaptation and pathogenicity is crucial for public health.

Purpose of the Study:

  • To assess the pathogenicity of an H5N1 avian influenza virus strain in mammals.
  • To investigate viral changes associated with increased mammalian pathogenicity.

Main Methods:

  • Infection of mice with A/chicken/Yamaguchi/7/2004 H5N1 strain.
  • Isolation and characterization of viruses recovered from infected mice.
  • Analysis of mutations in the PB2 protein (amino acid position 627).
  • Determination of mouse lethality and histopathological examination.

Main Results:

  • Recovered viruses from dead mice exhibited a glutamic acid to lysine substitution at PB2 position 627.
  • Mouse lethality increased approximately 5 x 10(4)-fold compared to the original virus.
  • Histopathological analysis revealed more rapid and severe tissue damage in mice infected with variant viruses.

Conclusions:

  • A specific mutation (PB2 E627K) in H5N1 avian influenza virus significantly enhances mammalian pathogenicity.
  • Characterizing recovered viruses is essential for evaluating their potential threat to mammals.
  • This study provides insights into the adaptive mechanisms of influenza viruses for mammalian hosts.

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