earticle

영어

Cell-surface glycans play key roles in mediating various molecular recognition events; aberrant glycosylation is implicated in disease progression. Therefore, probing the dynamic changes of glycan biosynthesis and structures is of great importance for augmenting our understanding of glycobiology and improving disease diagnosis and therapeutics. The metabolic glycan labeling was an appealing approach to incorporate specially designed carbohydrate analogs into the glycans, which enables the detection and imaging of the glycans in cells and living animals. However, one major bottleneck of this method is cell- type selectivity. Herein, we present the cell-specific metabolic glycan labeling using ligand-targeted liposomes to deliver unnatural sugars to target cells in a cell-surface receptor dependent manner. In this strategy, sugar analogs are encapsulated in ligand-targeted liposomes. The ligands bind to specific cell-surface receptors that are only expressed or up-regulated in target cells, which mediate the intracellular delivery of azidosugars via endocytosis. The delivered azidosugars are metabolically incorporated into cell-surface glycans and detected or imaged using a bioorthogonal reaction. The application of this strategy includes the facile introduction of myriad alternative ligands, as well as the cell-specific or tissue-specific imaging and detection of glycosylation in vivo.