Coordinated role of RIG-I, MDA5, and TLR7 in the innate immune response to duck hepatitis A virus 3

Arch Virol. 2025 Sep 24;170(10):211. doi: 10.1007/s00705-025-06384-5.

Abstract

The roles of RIG-I, MDA5, and TLR7 in duck hepatitis A virus genotype 3 (DHAV-3) infection were investigated using duck embryo fibroblasts (DEFs). DHAV-3 infection induced significant upregulation of RIG-I, MDA5, and TLR7 and high IFN-β, IL-6, and OASL responses. Overexpression and knockdown of RIG-I, MDA5, and TLR7 exerted significant effects on DHAV-3-induced IFN-β, IL-6, and OASL expression and DHAV-3 replication. Overexpression and inhibition of TLR7 altered DHAV-3-induced RIG-I and MDA5 expression. Together, these findings suggest that TLR7 and RIG-I/MDA5 play a coordinated role in detection and initiation of innate immunity against DHAV-3 infection.

Keywords: DHAV-3; MDA5; RIG-I; TLR7; innate immunity.

MeSH terms

  • Animals
  • DEAD Box Protein 58* / genetics
  • DEAD Box Protein 58* / immunology
  • Ducks / virology
  • Fibroblasts / immunology
  • Fibroblasts / virology
  • Hepatitis Virus, Duck* / genetics
  • Hepatitis Virus, Duck* / immunology
  • Hepatitis, Viral, Animal* / immunology
  • Hepatitis, Viral, Animal* / virology
  • Immunity, Innate*
  • Interferon-Induced Helicase, IFIH1* / genetics
  • Interferon-Induced Helicase, IFIH1* / immunology
  • Interferon-Induced Helicase, IFIH1* / metabolism
  • Interferon-beta / genetics
  • Interferon-beta / immunology
  • Picornaviridae Infections* / immunology
  • Picornaviridae Infections* / veterinary
  • Picornaviridae Infections* / virology
  • Poultry Diseases* / immunology
  • Poultry Diseases* / virology
  • Toll-Like Receptor 7* / genetics
  • Toll-Like Receptor 7* / immunology
  • Toll-Like Receptor 7* / metabolism
  • Virus Replication

Substances

  • Interferon-Induced Helicase, IFIH1
  • Toll-Like Receptor 7
  • DEAD Box Protein 58
  • Interferon-beta