• Airway Epithelium
• COPD Pharmacology
• COPD exacerbations mechanisms

Extracellular vesicles (EVs) are membranous nanosized particles that contain proteins, nucleic acids and lipids and are generated by nearly all cell types that participate in intercellular communication.1 The roles of EVs in pulmonary diseases are increasingly being recognised, and EVs have emerged as promising biomarkers for diagnosis and prognosis of cancer and acute and chronic respiratory diseases.2–4 In the field of regenerative medicine, stem/progenitor cell-derived EVs are proving revolutionary owing to their potential as cell-free strategies for tissue regeneration in many organs, including the lungs.5 6 More recently, EVs have been established as highly promising drug delivery vehicles with targeting abilities for specific tissues and cells, achieved through methods such as functionalisation of EV surfaces and modifying parent cells to obtain EVs that target particular cell types.7

The work by Kim et al in this issue of Thorax presents the development of surfactant protein A-coated extracellular vesicles (SP-A-EVs) as a novel drug delivery system that targets alveolar macrophages.8 SP-A is a hydrophilic protein, which is a major component of pulmonary surfactant secreted by alveolar type II cells and is known to modulate innate immune response to pathogens.9 SP-A has been previously shown to protect against interleukin …