Exosomal microRNA-21 derived from bronchial epithelial cells is involved in aberrant epithelium-fibroblast cross-talk in COPD induced by cigarette smoking

Rationale: Aberrant bronchial epithelium-fibroblast communication is essential for the airway remodeling that contributes to chronic obstructive pulmonary disease (COPD). Exosomes have emerged as novel mediators of intercellular communication, but their role in cigarette smoke (CS)-induced COPD is unknown. Here, we investigated the role of exosomal miR-21 in the dysfunctional epithelium-fibroblast cross-talk caused by CS.