CD63-snorkel tagging for isolation of exosomes
Chaoshan Han, Junjie Yang, Tingting Yin, Junqing An, Aijun Qiao, Yangpo Cao, Yuliang Feng, Haocheng Lu, Ying Wang, Liang Yang, Gangjian Qin
Abstract
Exosomes (Exo) are important mediators of inter-cellular communications; however, no effective method is available for isolating, thus characterizing, cellular-specific exosomes in vivo. Since CD63 is a reliable marker for exosomes, we have developed a tagging strategy, term “CD63-Snorkel (CD63-SNKL)”, in which CD63 at its intracellular C-terminus was fused to a fragment of PDGFRB that contains the transmembrane domain tethered to multiple epitope tags (HA, His, and FLAG) displayed in tandem on surface. We found that the CD63-SNKL protein has similar subcellular localizations as endogenous CD63 and can be effectively sorted into Exo. Furthermore, Exo secreted from CD63-SNKL–transduced cells can be effectively captured on anti-HA magnetic beads and eluted with HA peptides. Thus, CD63-SNKL may be engineered for isolating and tracking endogenous tissue-specific Exo in vivo.