Figure 4.

Macrophages are both producers and targets of extracellular vesicles (EVs). (A) Macrophage-derived EVs can contain inflammatory effector molecules (e.g., cytokines, chemokines, adhesion molecules, and proteases), which are involved in pathological hallmarks of COPD, such as alveolar wall destruction and emphysema [7,96,100,101]; (B) macrophages could also be the target of EVs. Emerging evidence shows that lung cells upon stimulation (e.g., cigarette extract) secrete EVs that target macrophages, influencing their polarization status and function [103,104,105,107].