Exosome are small vesicle excreted by cells that contain signalling factors. These may include microRNAs, mRNAs, hormones, and enzymes. These factors, which might not otherwise survive in environments such as the stomach or serum, are protected by the exosome. Exosomes may be taken up by a target cell, affecting a biochemical cascade. For example, exosomes may induce apoptosis1; up-regulate protein translation; and stimulate proliferation.
There are many ways to extract exosomes. Ultracentrifugation remains the gold standard, but can be time consuming and tedious. A more straightforward and efficient strategy, polyethylene glycol (PEG) precipitates the exosomes2. Does PEG affect the uptake of exosomes?
Using microscopic and functional evaluation, PEG does not affect exosome uptake. In Deregibus et al., a modified protocol was used to precipitate EVs3. These EVs improved proliferation and keratinocyte wound-closure. Zomer et al. show that exosome uptake increases tumor metastasis4. Several other groups demonstrate this in other tissue types5,6,7.
1. Claudiane Guay JKK, Sophie Rome, Véronique Menoud, Niels L Mulder, Angelika Jurdzinski, Francesca Mancarella, Guido Sebastiani, Alena Donda, Bryan J Gonzalez, Camilla Jandus, Karim Bouzakri, Michel Pinget, Christian Boitard , Pedro Romero , Francesco Dotta, Romano Regazzi Lymphocyte-Derived Exosomal MicroRNAs Promote Pancreatic β Cell Death and May Contribute to Type 1 Diabetes Development Cell metabolism 2019;29(2):348-361.
2. Mark A Rider SNH, David G Meckes Jr ExtraPEG: A Polyethylene Glycol-Based Method for Enrichment of Extracellular Vesicles Sci Rep 2016;6:23978.
3. Deregibus MC FF, D'Antico S, Manzini PM, Pasquino C, De Lena M, Tetta C, Brizzi MF, Camussi G. Charge-based precipitation of extracellular vesicles. . Int J Mol Med. 2016;38(5):1359-1366.
4. Anoek Zomer CM, Frederik Johannes Verweij, Alwin Kamermans, Ronny Schäfer, Evelyne Beerling, Raymond Michel Schiffelers, Elzo de Wit, Jordi Berenguer , Saskia Inge Johanna Ellenbroek, Thomas Wurdinger, Dirk Michiel Pegtel , Jacco van Rheenen In Vivo Imaging Reveals Extracellular Vesicle-Mediated Phenocopying of Metastatic Behavior Cell 2015;161(5):1046-1057.
5. Carriere J. BA, Darfeuille-Michaud A., Barnich N. & Nguyen H. T. Exosomes Released from Cells Infected with Crohn’s Disease-associated Adherent-Invasive Escherichia coli Activate Host Innate Immune Responses and Enhance Bacterial Intracellular Replication. Inflammatory bowel diseases 2016;22(3):516-528.
6. Jessian L Munoz SAB, Steven J Greco, Shakti H Ramkissoon, Keith L Ligon, Pranela Rameshwar. Delivery of Functional Anti-miR-9 by Mesenchymal Stem Cell-derived Exosomes to Glioblastoma Multiforme Cells Conferred Chemosensitivity Mol Ther Nucleic Acids 2013;2(10):e126.
7. Xiaomei Teng LC, Weiqian Chen, Junjie Yang, Ziying Yang, Zhenya Shen. Mesenchymal Stem Cell-Derived Exosomes Improve the Microenvironment of Infarcted Myocardium Contributing to Angiogenesis and Anti-Inflammation Cell Physiol Biochem 2015;37(6):2415-24.
