Fig. 1.

Exosome biogenesis. After endocytosis of the cargo, the early endosome undergoes a maturation process until finally the late endosome is originated, also known as multivesicular bodies (MVBs). During the process of maturation, dozens of intraluminal vesicles (ILVs) will be formed and gathered inside the MVBs. Finally, the MVBs will fuse with the plasma membrane, releasing to the extracellular space the ILVs, receiving now the name of “exosomes”. Alternatively, this MVBs can be targeted to the lysosome for degradation. Illustration created with the support of SMART (Servier Medical Art).