Identification of interferon-stimulated response elements (ISREs) in canines

Area of Science:

• Immunology
• Virology
• Molecular Biology

Background:

• Interferon (IFN) responses are critical for antiviral defense.
• Interferon-stimulated response elements (ISREs) regulate IFN signaling pathways.
• Canine ISRE research is limited compared to human and murine models.

Purpose of the Study:

• To elucidate the function of canine ISREs in IFN signaling.
• To develop a novel method for detecting canine IFN alpha (CaIFNα) activity.
• To evaluate the antiviral efficacy of recombinant CaIFNα.

Main Methods:

• Bioinformatic prediction of CaIFNα-responsive ISREs.
• Production of recombinant CaIFNα using the Pichia pastoris system.
• Development of an ISRE-driven enhanced green fluorescent protein (EGFP) reporter assay for flow cytometry.
• Viral suppression assays using vesicular stomatitis virus, canine influenza virus, and H9N2.

Main Results:

• CaIFNα was successfully produced and demonstrated antiviral activity against multiple viruses.
• Bioinformatics identified specific ISREs (ISRE2, ISRE8, ISRE10) activated by CaIFNα.
• The novel flow cytometry method accurately quantified CaIFNα levels with high sensitivity (0.1 × 10^-7 mg/mL).
• CaIFNα enhanced EGFP expression, confirming ISRE activation and gene augmentation.

Conclusions:

• Recombinant CaIFNα exhibits broad-spectrum antiviral activity.
• Specific canine ISREs mediate CaIFNα-induced gene expression.
• The developed flow cytometry assay provides a sensitive tool for CaIFNα detection.
• This research advances canine antiviral immunology and diagnostic capabilities for CaIFNα.