A1 Refereed original research article in a scientific journal
RIG-I Signaling Is Essential for Influenza B Virus-Induced Rapid Interferon Gene Expression
Authors: Sanna M. Mäkelä, Pamela Österlund, Veera Westenius, Sinikka Latvala, Michael S. Diamond, Michael Gale Jr., Ilkka Julkunen
Publisher: AMER SOC MICROBIOLOGY
Publication year: 2015
Journal: Journal of Virology
Journal name in source: JOURNAL OF VIROLOGY
Journal acronym: J VIROL
Volume: 89
Issue: 23
First page : 12014
Last page: 12025
Number of pages: 12
ISSN: 0022-538X
eISSN: 1098-5514
DOI: https://doi.org/10.1128/JVI.01576-15(external)
Recently, a great deal of interest has been paid to identifying the ligands for RIG-I under conditions of natural infection, as many previous studies have been based on transfection of cells with different types of viral or synthetic RNA structures. We shed light on this question by analyzing the earliest step in innate immune recognition of influenza B virus by human macrophages. We show that influenza B virus induces IRF3 activation, leading to IFN gene expression after viral RNPs (vRNPs) are released into the cytosol and are recognized by RIG-I receptor, meaning that the incoming influenza B virus is already able to activate IFN gene expression. In contrast, influenza A (H3N2) virus failed to activate IRF3 at very early times of infection, suggesting that there are differences in innate immune recognition between influenza A and B viruses.