Exosomes and exosome-mimetics as targeted drug carriers: Where we stand and what the future holds?

Abstract

Exosomes are a sub-group of extracellular vesicles, playing an important part in a cell-cell communication in many physiological and pathological conditions. Their size and competence for transferring material to recipient cells make them a promising nanocarrier for clinical use. Their non-immunogenic nature, similar to the body's own structure make them far superior transporters compared to liposomes and polymeric nanoparticles. This review, will provide an overview of exosome biogenesis, biological role, and purification methods. The focus of this manuscript will be to summarize specific applications of exosomes and exosome-mimetics as drug delivery systems in pharmaceutical drug development. We will describe drug-loading approaches, in vivo and in vitro exosome tracing methods, specific modifications and examples of the delivery of therapeutic and imaging molecules from a variety of biological origins. Challenges in the translation of exosome-based drug carriers to clinical use will also be discussed in this review.