Fig. 1

Pathways of exosome release. The process begins with the inward budding of the plasma membrane of endosomes, followed by transportation to early multivesicular endosomes (MVEs), which will undergo a series of changes into late MVEs with the accumulation of ILVs. After maturation, membranes of late MVEs generate and form vesicles that are 40–150 nm in size and contain various RNAs and proteins. Finally, the cargo of MVEs will be allocated to undergo two different pathways, delivered to lysosomes for degradation, or released into the extracellular milieu by fusing with the plasma membrane. The latter route gives rise to the production of exosomes