MicroRNA microarray between smoking-induced human bronchial epithelial cell (HBEC)-derived extracellular vesicles (EVs) and non-treated HBEC-derived Evs

To identify exosomal miRNAs that regulate smoking-induced lung myofibroblast differentiation, we conducted a miRNA microarray between smoking-induced HBEC-derived EVs and non-treated HBEC-derived EVs. Cigarette smoke extract (CSE) was prepared for smoking exposure model in vitro. Forty milliliters of cigarette smoke was drawn into the syringe and slowly bubbled into sterile serum-free cell culture media in a 15-ml BD falcon tube. One cigarette was used for the preparation of 10 mL of solution. CSE solution was filtered (0.22 μm) to remove insoluble particles and was designated as a 100% CSE solution. We analyzed the role of CSE induced HBEC-derived EVs in the airway microenvironment. After HBECs were incubated in the non-FBS containing medium with or without a low-concentration CSE (1.0%) for 2 days, we collected conditioned medium (on day 4, 6) and isolated EVs by ultracentrifugation. After then, we collected exosomal RNA and analyzed exosomal microRNA microarray.