What is an exosome?
Cells communicate beyond direct contact. Extracellular vesicles (EVs) are lipid-bounded structures released by cells that can carry proteins, lipids or nucleic acids. Exosomes are a subgroup defined by a particular intracellular origin.
The MISEV2023 consensus recommends broader EV terminology when origin has not been demonstrated. Small particle size or the word “exosome” on a label does not by itself establish identity or biological function.
A research field broader than one treatment
There are three distinct opportunities: studying tissue signals, using vesicles to deliver therapeutic cargo, and reading disease-related signals in diagnostic tests. These aims require different production methods, study designs and clinical assessments.
A test measuring gene expression in urinary vesicles and a product engineered to deliver siRNA are different clinical approaches. Success in one cannot be transferred to the other, particularly to an aesthetic serum.
Similar names, different contents
Live stem cells, PRP, conditioned medium, the secretome and a purified EV preparation are not interchangeable terms. When reading a study, consider the material’s source, isolation method and administration route together.
A useful research question goes beyond “Do exosomes work?”: which preparation, for which purpose, compared with what, and followed for how long? The rest of this portal applies those questions to specific human studies.