Two mutations in viral protein enhance the adaptation of waterfowl-origin H3N2 virus in murine model

Virus Res. 2019 Aug:269:197639. doi: 10.1016/j.virusres.2019.06.002. Epub 2019 Jun 4.

Abstract

After serial passage of a waterfowl-origin H3N2 subtype avian influenza virus in BALB/c mice, we obtained H3N2 mouse-adapted variants and identified eight amino acid substitutions in five viral proteins in our previous study. Here, we analyze the key mutations determining viral pathogenicity in mammals. We found that both PB2-D701N mutation and M1-M192V mutation were implicated in the viral pathogenic phenotypic variation of H3N2 avian influenza virus in mice. Furthermore, we found that PB2-D701N could enhance viral replication in vitro and in vivo and expanded viral tissue tropism. Our data suggest that PB2-D701N and M1-M192V are the virulence markers of H3N2 avian influenza virus, and these markers can be used in the trans-species transmission surveillance for the H3N2 avian influenza virus.

Keywords: Avian influenza virus; H3N2; Mice; Pathogenesis; Waterfowl.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptation, Physiological*
  • Animals
  • Disease Models, Animal
  • Dogs
  • Ducks / virology
  • Female
  • Influenza A Virus, H3N2 Subtype / genetics*
  • Influenza A Virus, H3N2 Subtype / pathogenicity
  • Influenza in Birds / transmission
  • Influenza in Birds / virology*
  • Madin Darby Canine Kidney Cells
  • Mice
  • Mice, Inbred BALB C
  • Mutation*
  • Serial Passage
  • Viral Tropism
  • Virulence Factors / genetics*

Substances

  • Virulence Factors