ExosomesNature’s Lipid Nanoparticles, a Rising Star in Drug Delivery and Diagnostics

Exosomes are a subgroup of nanosized extracellular vesicles
enclosed
by a lipid bilayer membrane and secreted by most eukaryotic cells.
They represent a route of intercellular communication and participate
in a wide variety of physiological and pathological processes. The
biological roles of exosomes rely on their bioactive cargos, including
proteins, nucleic acids, and lipids, which are delivered to target
cells. Their distinctive propertiesinnate stability, low immunogenicity,
biocompatibility, and good biomembrane penetration capacityallow
them to function as superior natural nanocarriers for efficient drug
delivery. Another notably favorable clinical application of exosomes
is in diagnostics. They hold various biomolecules from host cells,
which are indicative of pathophysiological conditions; therefore,
they are considered vital for biomarker discovery in clinical diagnostics.
Here, we use data from the CAS Content Collection and provide a landscape
overview of the current state and delineate trends in research advancement
on exosome applications in therapeutics and diagnostics across time,
geography, composition, cargo loading, and development pipelines.
We discuss exosome composition and pathway, from their biogenesis
and secretion from host cells to recipient cell uptake. We assess
methods for exosome isolation and purification, their clinical applications
in therapy and diagnostics, their development pipelines, the exploration
goals of the companies, the assortment of diseases they aim to treat,
development stages of their research, and publication trends. We hope
this review will be useful for understanding the current knowledge
in the field of medical applications of exosomes, in an effort to
further solve the remaining challenges in fulfilling their potential.