Exosomes are small vesicles that are secreted by various types of cells, known to mediate
signal transduction between cells. During recent years, novel carriers for the delivery of targeted
drugs, chemotherapy drugs and RNAs are under development, which is believed to be beneficial for
patients. Considering issues of drug nano-formulations in bloodstream, such as nano-toxicity and
rapid clearance by mononuclear phagocyte system, exosomes derived from either patient’s cells or
bodyfluids, seem to be an optimal option. This review presents the current patterns of drug-loaded
into exosomes and discusses how exosomes were reconstructed for targeted therapy. Loading either
exosomes directly or their donor cells is an alternative, including incubation, electroporation, transfection
of exosomes or transfection, incubation, activation of the parent cells. To solve the low efficiency
of cargo loading into exosomes, protein loading via optically reversible protein-protein interaction
can realize a novel exosomal protein carrier. In addition, targeted therapeutics with exosomes
is achieved by three means, via adding targeting peptides into the surface of exosomes, by transferring
specific genes within exosomes into tumors to establish a therapeutic target and, lastly, by targeting
at exosomes containing tumor associated antigens. Nevertheless, purification and mass production
of exosomes need further exploration, as well as more approaches were applied to targeted
therapy. Therefore, exosomes could serve as an effective tool for drug delivery and targeted therapy.
Overcoming physiological barriers by nanoparticles for intravenous drug delivery to the lymph nodes
