Figure 4.

Schematic drawing of two cells that communicate with each other by exchanging extracellular vesicles of different sizes and origins. Some vesicles directly bud from the plasma membrane (microvesicles, MVs), while exosomes (Exo) derive from the multivesicular body (MVB). For clarity, vesicles have been depicted in the same colour as the producing cell: yellow produced by the yellow cell (A), and light blue produced by the light blue cell (B). After release, some EVs are quickly lysed and release their content into the extracellular space (lower enlarged view). Some of them contain matrix metalloproteases and other hydrolytic enzymes responsible for the digestion of various ECM components. Alternatively, intact EVs can interact with the target cells that can internalize them through a variety of pathways [145]. The vesicles can also directly fuse with the plasma membrane of the target cell. Both MVs and exosomes are endowed with proteins, lipids, and nucleic acids that can influence different physiological and pathological functions of the target cell (upper enlarged view).