Endocrine Abstracts

The term Extracellular Vesicles (EVs) encompasses all those vesicular structures (surrounded by a cell membrane) released into the extracellular environment. Virtually all cells are capable of producing EVs through highly conserved mechanisms in evolution. These vesicles serve as a communication channel between different cells of the organism due to their capacity to exchange biomolecules, including proteins, lipids, nucleic acids or carbohydrates. Their membranous packaging gives protection to these molecular messengers, and would provide selectivity to reach possibly distant cells in the organism. Although described in the 80’s, the interest in EVs re-emerged in 90’s with the description of their ability to present antigens and thus amplify the immune response. Later, the observation that RNA was contained in vesicles pointed to their role as mediators of intercellular communication. Also, as EV composition is dependent on active mechanisms of protein and nucleic acids recruitment, the presence of specific characteristics on the released material spotted on the search for biomarkers of several diseases. Several studies provided evidence that EVs in biological fluids are good source of potential biomarkers for metabolic diseases. Yet, their use as diagnostic and prognostic biomarkers in clinical practice still needs further validation. Importantly, although different isolation methods have been developed for the study of EVs, most of them do not preclude the presence of non-vesicular contaminants. Therefore, it is still necessary to define a consensus technique to overcome the variability of results obtained depending on the technique used. Ideally, this technique must take into account the final objective of the EV preparation (biomarker determination, therapeutic approach, …). An overview of EVs, from their description, methods of isolation and analysis, and application in biomarker discovery will be discussed.