TY - JOUR T1 - Effects of Lyophilization of Arginine-rich Cell-penetrating Peptide-modified Extracellular Vesicles on Intracellular Delivery JF - Anticancer Research JO - Anticancer Res SP - 6701 LP - 6709 DO - 10.21873/anticanres.13885 VL - 39 IS - 12 AU - KOSUKE NOGUCHI AU - MAMI HIRANO AU - TAKUYA HASHIMOTO AU - EIJI YUBA AU - TOMOKA TAKATANI-NAKASE AU - IKUHIKO NAKASE Y1 - 2019/12/01 UR - http://ar.iiarjournals.org/content/39/12/6701.abstract N2 - Background/Aim: Extracellular vesicles (exosomes, EVs) (30-200 nm in diameter) are secreted by various cells in the body. Owing to the pharmaceutical advantages of EVs, an EV-based drug delivery system (DDS) for cancer therapy is expected to be the next-generation therapeutic system. However, preservation methods for functional and therapeutic EVs should be developed. Here, we developed the method of lyophilization of arginine-rich cell penetrating peptide (CPP)-modified EVs and investigated the effects of lyophilization on the characteristics of EVs. Materials and Methods: Particle size, structure, zeta-potential, and cellular uptake efficacy of the arginine-rich CPP-modified EVs were analyzed. The model protein saporin (SAP), having anti-cancer effects, was encapsulated inside the EVs to assess the cytosolic release of EV content after cellular uptake. Results: Lyophilization of the EVs did not affect their particle size, structure, zeta-potential, and cellular uptake efficacy; however, the biological activity of the encapsulated SAP was inhibited by lyophilization. Conclusion: Lyophilization of EVs may affect SAP structures and/or reduce the cytosolic release efficacy of EV's content after cellular uptake and needs attention in EV-based DDSs. ER -