Exosome (vesicle)

Exosomes are approximately 30 to 90 nm-sized vesicles which are emitted from a cell to the environment. They can be formed inter alia by lymphoid cells, platelets, mast cells, dendritic cells, neurons, astrocytes and tumor cells. Exosomes are formed in a multistep process involving constriction of the cell membrane, called endocytosis, and an outward transfer, a so-called exocytosis. These vesicles contain, among other nucleic acids and proteins of varying composition and serve as transport vehicles and for discharging of cell components. In addition, they serve the cellular communication. Thus, exosomes may play a role in acquired immunity. But viruses, such as the HI -virus, use exosomes to transport and camouflage. Exosomes are currently being investigated as a possible therapeutic options in the treatment of autoimmune diseases and cancer.