Omal marker amount of the leptin-loaded exosome prepared below optimized condition were similar to these of bare exosome. Drug-loading efficiency was 7 in this condition. Even though 50 of leptin burst from the exosome immediately after release study and 70 of leptin was degraded by protease challenge test, the other leptin was thought of to become retained inside the exosome. Particle-size distribution and leptin concentration of the exosome had been steady at four for 1 month. Summary/RAR/RXR Proteins Recombinant Proteins Conclusion: This methodology to load protein drugs into exosome is promising technique for its drug delivery application.PS01.Characterization and in vivo imaging of mesenchymal stem cells derived extracellular vesicle Cheng-Hsiu Lu, Yi-An Chen, Chien-Chih Ke and Ren-Shyan Liu National Yang-Ming university, Taipei, Taiwan (Republic of China)therapeutic and paracrine effects of MSCs. With all the fast raise of consideration and getting of good potential as a future healthcare regimen for human disease, the information of fate and behaviour of EVs inside the living topic ought to be urgently gathered. On the other hand, investigators nevertheless have not developed an efficient method to monitor the in vivo behaviour of EVs. As a result, here in our study, EVs derived from Wharton’s jelly MSCs were isolated, characterized and radiolabeled with 111In-oxine followed by biodistribution study and in vivo SPECT/CT imaging. Techniques: Conditioned medium was collected followed by exosome isolation making use of Exo-Prep kit (Hansa BioMed) followed by purification with PD10 columns and one hundred kDa concentration. Expression of EVs particular proteins CD63 and HSP70 was verified by western blot. Morphology and size have been characterized by transmission electron microscopy nanoparticle tracking analysis (NTA). For radiolabeling, EVs have been incubated with 111In-oxine in PBS at 37oc for 1 h followed by purification and further characterization. Biodistribution and in vivo SPECT/CT imaging of 111In-oxine- labelled EVs have been performed at 1, three, six and 24 h following intravenous injection into C57BL/6 mice. Benefits: CD63 and HSP70 expression were observed on EVs as well as 111In-oxine-EVs. Radiochemical purity of 111In-oxine-EVs as higher than 90 and remained stable for a minimum of 48 h. Result of biodistribution showed that 111In-oxine-labelled EVs accumulated in liver, spleen, bone marrow and cleared swiftly from the CD66c/CEACAM6 Proteins Accession circulation. In vivo SPECT/CT imaging of 111In-oxine-labelled EVs showed high accumulation in liver, bone, spleen and liver, but not in brain and circulation. Summary/Conclusion: In this study, we’ve preliminarily demonstrated the feasibility of in vivo tracking of MSC- derived EVs labelled with 111Inoxine. Additional investigation continues to be required and underway to monitor the in vivo fate and behaviour of EVs.PS01.EVs as siRNA delivery automobiles for functional knockdown in cells Senny Nordmeier, Victoria Portnoy and Frank Hsiung System Biosciences, Palo Alto, USAIntroduction: Mesenchymal stem cells (MSCs) are multipotent stromal cells which show the great possible in tissue engineering, regenerative medicine along with the therapy of various ailments. Deep into mechanisms, paracrine impact has been reported to become the major part in MSC therapy. Additional, extracellular vesicles (EVs) are reportedly the major player mediating theIntroduction: Extracellular vesicles (EVs) mediate cellto-cell communication by delivering cargo, composed of nucleic acids, proteins and different other molecules, from secreting cells to precise tissues and recipientJOURNAL OF.