Abstract
BACKGROUND: Respiratory diseases are increasing global health burden with persistently high morbidity and mortality. Extracellular vesicles (EVs), which are virtually released by all cell types and carry a variety of molecules like miRNAs, have emerged as crucial mediators of intercellular communication. They play a key role in maintaining lung homeostasis and are involved in the pathogenesis of various respiratory conditions. Furthermore, mesenchymal stromal cell-derived EVs (MSC-EVs) have shown significant therapeutic potential due to their anti-inflammatory, antimicrobial, and reparative properties. METHODS: This narrative review critically assesses the current body of literature on the roles of EVs in respiratory diseases. We examine evidence from pre-clinical and clinical studies that investigate EVs as biomarkers and therapeutics for conditions including asthma, bronchopulmonary dysplasia (BPD), chronic obstructive pulmonary disease (COPD), cystic fibrosis (CF), idiopathic pulmonary fibrosis (IPF), lung cancer, and pulmonary arterial hypertension (PAH). RESULTS: EVs reflect the physiological or pathological state of their parental cells, making them promising multimodal biomarkers for the early diagnosis and monitoring of disease progression. Additionally, MSC-EVs function as effective, cell-free therapeutic agents. In a variety of disease models, they demonstrate efficacy by modulating immune responses, enhancing alveolar fluid clearance, and restoring epithelial and endothelial barrier integrity, leading to improved survival and outcomes. CONCLUSIONS: EVs hold a dual and transformative potential in respiratory medicine. They may serve as valuable diagnostic and prognostic tools, and their application as cell-free therapeutics represents a novel and promising strategy for treating a wide spectrum of debilitating respiratory diseases.