Increased Target Cell Selectivity of Exosome Modified with Glycan Polymers

Exosomes are secreted from a variety of cells and transmit parental cell-derived biomolecules to recipient cells in distant organs. Although they are expected to serve as natural drug carriers, the use of exosomes as drug delivery tools is limited due to the low uptake efficiency by the target cells, degradation of the contents of exosome in the lysosome, and possible adverse effects caused by the delivery to non-target cells. Among them, target cell selectivity is most critical for developing exosome-based novel treatment modality. We are interested in the compositions of glycans on the surface of exosome that determine the selective delivery to target cells. For example, we have succeeded, by modifying exosomes with a lactose-carrying polymer, to enhance their selective delivery to parenchymal hepatocytes through asialoglycoprotein receptors that recognize galactose.