2019/01/17
Exosomes: toward single-particle analysis of the cellular “Deliveroo” system of the body
The Exosome Laboratory of CIC bioGUNE, led by Dr. Juan Manuel Falcón, has published two articles in the journal Nanoscale, a reference in nanotechnology research. In collaboration with Dr. Sergei Kruglik of the Laboratoire Jean Perrin, Sorbonne Université (Paris), they have described a novel application of RAMAN spectroscopy, to define the composition of sub-populations of extracellular vesicles including exosomes and microvesicles. An independent article, in collaboration with Dr Jordi Llop, principal investigator of the Nuclear Imagen Department at CIC biomaGUNE, describes how the extracellular vesicles of hepatic origin are distributed in a living organism, and more interestingly, how specific modifications of the surface alter their fate in the organism.
The research about extracellular vesicles is growing exponentially, and there are good reasons for that. Released to the external environment by all types of cells, they are membrane-enclosed entities that contain a distinctive cargo determined by their parental cell. Moreover, they transport metabolic enzymes and signals to specific acceptor cells modifying extracellular and intracellular metabolisms. As they circulate, we can intercept them and decipher the messages between different tissues, ranging from survival kits for damaged cells, to niche-promoters that favour metastases released by cancer cells. "Not only do they give us information" - clarifies Dr. Falcón - "In the future, we would modify these vesicles to go to a specific organ, loaded with antitumor drugs or specific enzymes to help the tissue to overcome a disease".
Toward those direction points the results obtained in collaboration with CIC biomaGUNE, the institution of reference in biomaterials at the Basque Scientific Network. By modifying the surface of the vesicles, an increase in their preference for the lung and for the axillary lymph nodes is produced. Their result support that chemical modifications of the surface of these vesicles will allow us to target specific tissues, selectively.
To decipher the complex communication network established by these extracellular vesicles, it will require methods able to describe single vesicle composition. In this context, RAMAN spectroscopy is unique because from a single particle (or small group of particles) can obtain its global molecular composition, in terms of proteins, lipids, sugars and nucleic acids. The article now published, shows the application of this methodology to characterize the exosomes heterogeneity of complex bodily fluids such as urine.
Dr. Juan Manuel Falcón investigates exosomes since 2005 at the CIC bioGUNE. Belongs to the CIBER network of liver and digestive diseases, and it is an IKERBASQUE Research professor since 2010. His complete bibliography and contact email can be found on the institute's website.
Articles referenced are in advance of publication in the journal Nanoscale (Sergey et al. Nanoscale 2019, DOI: 10.1039 / C8NR04677H, and Royo et al., Nanoscale 2019, DOI: 10.1039 / C8NR03900C)
The left panel shows a scheme of extracellular vesicles secretion including exosomes, microvesicles and apoptotic bodies, as well as images of electron microscopy and RAMAN spectroscopy of a small group of exosomes.
The right panel shows the bio-distribution in a mouse of extracellular vesicles Iodie-124-labelled and injected intravenously.