H5N1 and H9N2 viruses are important causes of avian influenza in China. H5N1 is typically associated with severe to fatal disease in poultry, while H9N2 is usually associated with mild disease. Differences in viral virulence prompted us to investigate whether innate immune responses would be differentially regulated following infection by H5N1 and H9N2 viruses. To address this hypothesis, expression of a panel of innate immune-related genes including IFN-α, IFN-β, Mx1, OASL, ISG12, IFIT5, IRF7, USP18, SST, and KHSRP in immortal DF-1 cells following H5N1 and H9N2 infection was analyzed and compared by real-time quantitative RT-PCR. Cells infected by either virus overall exhibited a similar expression profile for four ISGs (Mx1, OASL, ISG12, and IFIT5), IFN-α, IFN-β, and SST gene. However, two immune-regulatory genes (IRF7 and KHSRP) were not responsive to highly pathogenic H5N1 infection but were strongly up-regulated in DF-1 cells infected with low pathogenic H9N2 infection. The subtype-dependent host response observed in this study offers new insights into the potential roles of IRF7 and KHSRP in control and modulation of the replication and virulence of different subtypes or strains of avian influenza A virus.
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|Published - Apr 1 2015
Bibliographical noteFunding Information:
We thank anonymous reviewers for helpful comments on this manuscript. The study was supported by International Science & Technology Cooperation Program of China (2014DFA31900), Funded by Shandong Modern Agricultural Technology & Industry System (SDAIT-13-011-01), Special fund for Agro-scientific research in the public interest (201303046-06), Innovation Project of Shandong Academy of Agricultural Sciences (2014CXZ08) and Taishan Scholar Program.
© 2014, The Author(s).
- Innate immune-related genes
- Real-time quantitative PCR
- Subtype-dependent host response
ASJC Scopus subject areas
- Molecular Biology