Authors: Vasiliy S Chernyshev Rakesh Rachamadugu Yen Hsun Tseng David M Belnap Yunlu Jia Kyle J Branch Anthony E Butterfield Leonard F Pease Philip S Bernard Mikhail Skliar
Publish Date: 2015/03/28
Volume: 407, Issue: 12, Pages: 3285-3301
Abstract
Exosomes are stable nanovesicles secreted by cells into the circulation Their reported sizes differ substantially which likely reflects the difference in the isolation techniques used the cells that secreted them and the methods used in their characterization We analyzed the influence of the last factor on the measured sizes and shapes of hydrated and desiccated exosomes isolated from the serum of a pancreatic cancer patient and a healthy control We found that hydrated exosomes are closetospherical nanoparticles with a hydrodynamic radius that is substantially larger than the geometric size For desiccated exosomes we found that the desiccated shape and sizing are influenced by the manner in which drying occurred Isotropic desiccation in aerosol preserves the nearspherical shape of the exosomes whereas drying on a surface likely distorts their shapes and influences the sizing results obtained by techniques that require surface fixation prior to analysisThe authors are indebted to Brian F Woodfield of Brigham Young University Department of Chemistry for providing access to the NTA instrument The authors acknowledge financial support from the National Science Foundation award number IGERT0903715 and the University of Utah Department of Chemical Engineering Seed Grant and the Graduate Research Fellowship awardMS and PSB conceived the study RR isolated exosomes VSC and RR performed NTA measurements DLS measurements were performed by VSC and MS DMB performed cryoTEM imaging SEM imaging was performed by YJ and VSC electrospray DMA measurements were performed by YHT VSC LFP and MS VSC and MS analyzed the experimental results AEB wrote the MATLAB code to analyze the imaged exosomes MS performed statistical analysis and VSC and KJB performed manual sizing of the imaged exosomes The manuscript was written by VSC and MS and was edited by all authors
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