Host Regulatory Network Response to Infection with Highly Pathogenic H5N1 Avian Influenza Virus

Over the last decade, more than half of humans infected with highly pathogenic avian influenza (HPAI) H5N1 viruses have died, and yet virus-induced host signaling has yet to be clearly elucidated. Airway epithelia are known to produce inflammatory mediators that contribute to HPAI H5N1-mediated pathogenicity, but a comprehensive analysis of the host response in this cell type is lacking. Here, we leveraged a systems approach to identify and statistically validate signaling sub-networks that define the dynamic transcriptional response of human bronchial epithelial cells after infection with influenza A/Vietnam/1203/2004 (H5N1, VN1203). Importantly, we validated a subset of transcripts from one sub-network in both Calu-3 cells and mice. A more detailed examination of two sub-networks involved in the immune response and keratinization processes revealed potential novel mediators of HPAI H5N1 pathogenesis and host response signaling. Finally, we show how these results compare with a less virulent strain of influenza virus. Using emergent network properties, we provide fresh insight into the host response to HPAI H5N1 virus infection, and identify novel avenues for perturbation studies and potential therapeutic intervention of fatal HPAI H5N1 disease.