Snorkel-tag Based Affinity Chromatography for Recombinant Extracellular Vesicle Purification

Extracellular vesicles (EVs) are lipid nanoparticles and play an important role in cell-cell communications, making them potential therapeutic agents and allowing to engineer for targeted drug delivery. The expanding applications of EVs in next generation medicine are still limited by existing tools for scaling standardized EV production, single EV tracing and analytics, and thus provide only a snapshot of tissue-specific EV cargo information. Here, we present CD81, an EV surface marker protein, genetically fused to series of tags with additional transmembrane domain to be displayed on the EV surface, which we term Snorkel-tag. This system enables to affinity purify EVs from complex matrices in a non-destructive form. In future applications, this strategy will allow generating transgenic animals to enable tracing and analyzing EVs, and their cargo in physiological and pathophysiological set-ups, and facilitate the development of EV based diagnostic tools in murine models which can be translated to humans. ### Competing Interest Statement Johannes Grillari and Regina Grillari are co-founder and shareholder of Evercyte GmbH. Matthias Hackl serves as a CEO and co-founder, Johannes Grillari and Regina Grillari are co-founders and serves on the scientific advisory board of TAmiRNA GmbH. Andre Gorgens, Dhanu Gupta and Samir EL Andaloussi are consultants for and have equity interests in Evox Therapeutics Ltd., Oxford, United Kingdom. All other authors declare no potential conflict of interests.