AUTHOR=Huang Chun-Chieh , Kang Miya , Debnath Koushik , Leung Kasey , Raghavan Vidhath , Lu Yu , Cooper Lyndon F. , Gajendrareddy Praveen , Ravindran Sriram 

TITLE=Functionality of lyophilized osteoinductive EVs: a mechanistic study

JOURNAL=Frontiers in Bioengineering and Biotechnology

VOLUME=Volume 12 - 2024

YEAR=2024

URL=https://www.frontiersin.org/journals/bioengineering-and-biotechnology/articles/10.3389/fbioe.2024.1452428

DOI=10.3389/fbioe.2024.1452428

ISSN=2296-4185

ABSTRACT=Mesenchymal stem cell derived extracellular vesicles (MSC EVs) possess immense therapeutic potential. Us and others have characterized EV bioactivity mechanistically as well as devised approaches to engineer EVs for regenerative medicine applications. For these advances to be clinically relevant, translational approaches to EV therapeutics need to be evaluated and established. Long-term stability and storage of purified EVs by lyophilization is one of the major hurdles facing translation of EV therapeutics. While current studies have focused extensively on the biophysical characterization of the lyophilized EVs, the functional, mechanistic and in vivo functionality of the EVs has remained understudied. Using functionally engineered osteoinductive EVs developed and characterized in our laboratory, in this study, we have endeavored to compare the functional and mechanistic bioactivity of fresh and lyophilized EVs in vitro and in vivo using dimethyl sulfoxide (DMSO) as a cryoprotectant. Results presented here highlight the ability of DMSO to maintain the functional stability of the engineered EVs in vitro and in vivo and serve as a baseline for its potential in EV therapeutics. Future studies can focus on expanding this knowledge to test other cryoprotectants as well as functionality of lyophilized naïve and engineered EVs in regeneration of multiple other tissues.