Reagents | REAGENT

Extracellular vesicles (EVs) are membrane-like natural nanoparticles released by all cell types and present in all biological fluids. Generally, EVs are roughly divided into three subtypes according to their biological pathways-microvesicles (MVs), exosomes and apoptotic bodies, size, content and biological functions [1], [2]. In addition to this classification, various subgroups of vesicles have gradually emerged, especially various types of exosomes [3]. As very natural EVs contain biologically active molecules as cargo from their production cells. As their own nanoparticles, EVs inherently benefit from immune tolerance, stability of the circulatory system, and the ability to cross biological barriers to reach distant organs such as the brain [2], [4]. [1], [5]. These The horizontal transfer of macromolecules makes EVs an important medium for cell-to-cell communication and can be used therapeutically [1], [2], [5]. Using EVs as nanocarriers further provides specific bioengineering for them to carry Possibility of therapeutic cargo molecules. The technology of loading goods into EVs can be roughly divided into two basic methods: exogenous and endogenous loading. Exogenous loading usually involves incorporation or loading of cargo into the pre-separation of EVs by various methods, including co-incubation, sonication, and electroporation [2], [6], [7]. For endogenous loading, parental cells are genetically engineered to overexpress the required RNA or protein, with or without specific ones, and then integrated into secreted vesicles during EV biogenesis [2], [6 ], [8], [9].

In order to accurately determine the therapeutic potential of engineered EVs, well-designed in vivo applications are essential. In order to correctly measure the therapeutic effect, kinetics and kinetics of the cargo carried by EVs, accurate and reliable drug delivery strategies are essential. However, to date, the field of therapeutic EV research has been affected by inconsistencies in all areas of EV production, including methods for EV isolation, quantification, and characterization [10]. Standardized, simplified, and clearly defined processes in EV manufacturing are the key to reliable therapeutic EVs administered in preclinical and clinical settings.

This review aims to briefly list the currently used methods of EV administration, discuss their potential quantification techniques, and identify possible pitfalls related to these methods. The advantageous dosage strategy is based on the EV quantification method, which is first tailored to the EV engineering strategy, parent cell type and isolation method, and secondly tailored to the in vivo experimental applications and potential scientific issues. In 2017, an international consortium published a meta-analysis of more than 1,000 studies from various fields of EV research, revealing the wide heterogeneity of EV isolation methods [10]. They reported 190 unique isolation methods and 1,038 unique solutions for extracting EVs from biological fluids, but the documentation was insufficient for the determination of the main experimental parameters. This study strongly shows that despite the large number of available EV isolation, quantification, and characterization methods, universally applicable and standardized protocols are still elusive. Therefore, when designing an EV dosing strategy for in vivo application, please consider carefully. And you need to pay attention to the experimental parameters and EV characteristics.

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