Exosomes

Definition

Exosomes are small extracellular vesicles released by cells that can carry proteins, lipids, nucleic acids, and other molecular cargo. They are often described as a subtype of extracellular vesicle formed through the endosomal pathway, although isolating and proving a vesicle is specifically an exosome can be technically challenging. [1] [2] [3]

Why It Matters in Ageing Research

Exosomes matter because they are one way cells communicate with nearby and distant tissues. In ageing research, extracellular vesicles are studied for their roles in inflammation, tissue repair, immune signalling, senescence-associated communication, biomarker discovery, and regenerative medicine. Their therapeutic potential is an active research area, but clinical claims about exosome products often run ahead of standardisation, dosing, safety, and evidence. [4] [5] [6]

Common Confusion

• Exosomes are not the same as stem cells; they are vesicles released by cells.
• Not every extracellular vesicle isolated from a sample can automatically be called an exosome.
• Exosome-based therapies remain an active research area, not a general anti-ageing treatment with established clinical benefits.

Related Reading

• Hallmarks of Ageing
• Intercellular Communication
• Stem Cell Exhaustion
• Cellular Senescence

References

1. Kalluri, R., & LeBleu, V. S. (2020). The biology, function, and biomedical applications of exosomes. https://doi.org/10.1126/science.aau6977
2. Doyle, L. M., & Wang, M. Z. (2019). Overview of Extracellular Vesicles, Their Origin, Composition, Purpose, and Methods for Exosome Isolation and Analysis. https://doi.org/10.3390/cells8070727
3. Théry, C., et al. (2018). Minimal information for studies of extracellular vesicles 2018: a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines. https://doi.org/10.1080/20013078.2018.1535750
4. Xu, R., Rai, A., Chen, M., Suwakulsiri, W., Greening, D. W., & Simpson, R. J. (2018). Extracellular vesicles in cancer — implications for future improvements in cancer care. https://doi.org/10.1038/s41571-018-0036-9
5. Borras, F. E., & Edelman, E. R. (2021). Extracellular Vesicles and Aging: A Decade of Discovery and Potential Therapeutic Applications. https://doi.org/10.3390/cells10082077
6. Kumar, M. A., et al. (2024). Extracellular vesicles as tools and targets in therapy for diseases. https://doi.org/10.1038/s41392-024-01735-1