Figure 1.

Function and processing of exosomes. Substances are encapsulated using endocytosis forming the early endosomes, which further mature into ILV-containing MVBs. The formation of ILVs is mediated by mechanisms that depend on the ESCRT. ILVs subsequently merge with the cell membrane via an adenosine triphosphate-dependent process, thus releasing exosomes outside the cells. These exosomes travel through biological fluids. circRNA, circular RNA; ILV, intraluminal vesicle; MVB, multivesicular body; ESCRT, endosomal sorting complex required for transport.