Table 1.

The characteristics of extracellular vesicles in the respiratory system.

Source	Function	Reference
Bronchial epithelial cells	Regulate the normal airway biology including homeostasis and innate defense	[36]
Macrophages	Maintain homeostasis and immune cell production	[38]
Endothelial cells	Activate neighboring pericytes through proinflammatory microRNAs	[39]
B cells	Activate immune system through antigen presentation	[40]
Dendritic cells	Modulate immune reactions through activating T and B cells	[41,42]
Mesenchymal stromal cells	Modulate the polarization of macrophages	[43]