Transcriptomics profile of human bronchial epithelial cells exposed to influenza virus (H3N2) and ambient fine particles
Fine particulate matter (PM2.5) pollution remains a major threat to public health. As the physical barrier against inhaled air pollutants, airway epithelium is a primary target for PM2.5 and influenza viruses, two major environmental insults. Recent studies have shown that PM2.5 and influenza viruses may interact to aggravate airway inflammation, an essential event in the pathogenesis of diverse pulmonary diseases. Airway epithelium plays a critical role in lung health and disorders. Thus far, the mechanisms for the interactive effect of PM2.5 and the influenza virus on gene transcription of airway epithelial cells have not been fully uncovered. In this present pilot study, the transcriptome sequencing approach was introduced to identify responsive genes following individual and co-exposure to PM2.5 and influenza A (H3N2) viruses in a human bronchial epithelial cell line (BEAS-2B). Enrichment analysis revealed the function of differentially expressed genes (DEGs). Specifically, the DEGs enriched in the xenobiotic metabolism by the cytochrome P450 pathway were linked to PM2.5 exposure. In contrast, the DEGs enriched in environmental information processing and human diseases, such as viral protein interaction with cytokines and cytokine receptors and epithelial cell signaling in bacterial infection, were significantly related to H3N2 exposure. Meanwhile, this study found that co-exposure to PM2.5 and H3N2 may affect G protein-coupled receptors on the cell surface by modulating Ca2+. Thus, the results from this study provides insights into PM2.5- and influenza virus-induced airway inflammation and potential mechanisms Overall design: The transcriptome sequencing approach was introduced to identify responsive genes following individual and co-exposure to PM2.5 and influenza A (H3N2) viruses in a human bronchial epithelial cell line (BEAS-2B). The cells were subjected to the following treatments: serum-free medium (control group, mock), PM2.5 (12.5 µg/mL), H3N2 (MOI=1), or co-exposure of PM2.5 (12.5 µg/mL) and H3N2 (MOI=1).