Exosomes are generated through a process called endocytosis. The cell’s membrane invaginates to form early endosomes, which then mature into multivesicular bodies (MVBs). These MVBs contain small vesicles inside them, which eventually become exosomes.

 

Exosome Cargo
During the formation of multivesicular bodies, various molecules are selectively incorporated into the exosomes. These can include proteins, lipids, and genetic material (such as RNA). The specific cargo loaded into exosomes depends on the type and condition of the cell.

 

Release of Exosomes
Exosomes are released from the cell when the multivesicular bodies fuse with the cell’s plasma membrane. This releases the exosomes into the extracellular space.

 

Intercellular Communication
Once released, exosomes can travel through the extracellular fluid and interact with nearby or distant cells. They can be taken up by neighboring cells through various mechanisms, such as endocytosis or membrane fusion.

 

Cellular Response
The internalized exosomes deliver their cargo to the recipient cells, potentially influencing their function. The transferred molecules may affect signaling pathways, gene expression, and cellular behavior. This communication mechanism is believed to allow cells to coordinate their activities and respond to changes in their environment.

 

Physiological and Pathological Functions
Exosomes play essential roles in various physiological processes, including immune response regulation, tissue repair, and development. They are also implicated in pathological conditions such as cancer, neurodegenerative diseases, and inflammatory disorders.