title: Extracellular vesicles as drug delivery systems: lessons from the liposome field.
abstract: Extracellular vesicles (EVs) are membrane-derived particles surrounded by a (phospho)lipid bilayer that are released by cells in the human body. In addition to direct cell-to-cell contact and the secretion of soluble factors, EVs function as another mechanism of intercellular communication. These vesicles are able to efficiently deliver their parental cell-derived molecular cargo to recipient cells, which can result in structural changes at an RNA, protein, or even phenotypic level. For this reason, EVs have recently gained much interest for drug delivery purposes. In contrast to these 'natural delivery systems', synthetic (phospho)lipid vesicles, or liposomes, have been employed as drug carriers for decades, resulting in several approved liposomal nanomedicines used in the clinic. This review discusses the similarities and differences between EVs and liposomes with the focus on features that are relevant for drug delivery purposes such as circulation time, biodistribution, cellular interactions and cargo loading. By applying beneficial features of EVs to liposomes and vice versa, improved drug carriers can be developed which will advance the field of nanomedicines and ultimately improve patient outcomes. While the application of EVs for therapeutic drug delivery is still in its infancy, issues regarding the understanding of EV biogenesis, large-scale production and in vivo interactions need to be addressed in order to develop successful and cost-effective EV-based drug delivery systems.
authors.affiliation: Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Roy
authors.initials: R
authors.lastname: van der Meel
authors.affiliation: Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Marcel H A M
authors.initials: MH
authors.lastname: Fens
authors.affiliation: Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, Utrecht, The Netherlands; Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK.
authors.forename: Pieter
authors.initials: P
authors.lastname: Vader
authors.affiliation: Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Wouter W
authors.initials: WW
authors.lastname: van Solinge
authors.affiliation: Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109, USA.
authors.forename: Omolola
authors.initials: O
authors.lastname: Eniola-Adefeso
authors.affiliation: Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, Utrecht, The Netherlands. Electronic address: r.schiffelers@umcutrecht.nl.
authors.forename: Raymond M
authors.initials: RM
authors.lastname: Schiffelers
mesh_terms: D000818:Animals; D055252:Cell-Derived Microparticles; D016503:Drug Delivery Systems; D006801:Humans; D008081:Liposomes
chemical_list: D008081:Liposomes
keywords: Drug delivery; Drug targeting; Exosomes; Extracellular vesicles; Liposomes; Nanomedicines