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Extracell Vesicles Circ Nucleic Acids 2020;1:20-56 I http://dx.doi.org/10.20517/evcna.2020.10 Page 39

Conclusions: We developed a simple, robust and quantitative workflow for isolating and analyzing EV
proteins. EVs obtained by membrane-affinity spin columns were enriched in the relevant EV proteins and
depleted for non-EV proteins, establishing a method for easy compliance with official MISEV guidelines.

24. Nanomechanical fingerprinting of single extracellular vesicles

Authors: Shivani Sharma
E-mail: sharmas@cnsi.ucla.edu
Affiliations:
Department of Pathology & Laboratory Medicine, David Geffen School of Medicine, University of California
Los Angeles, Los Angeles, USA.
Jonsson Comprehensive Cancer Center, University of California Los Angeles, Los Angeles, CA, USA.
Abstracts: As potential a class of novel diagnostics and therapeutics, the physio-chemical characterization
as well as the biomolecular composition of EVs are widely investigated. However, there is emerging
evidence suggesting that biomechanical analysis of lipid-bilayer membrane-bound single EVs may provide
key insights into their biological structure, biomarker functions, and potential therapeutic functions. Using
multi-parametric AFM imaging and force spectroscopy we compared the structure-mechanical properties
(including Young’s modulus, stiffness, deformability, and adhesion maps) of invasive and noninvasive
breast cancer EVs at nanoscale resolution. Our findings reveal that secreted EVs reflect the biomechanical
signatures of parent cancer cells that vary in invasive potential. Irrespective of the EV isolation method
employed, single EVs derived from non- invasive (biomechanically stiffer) cancer cells were also
significantly biomechanically distinct compared to EVs derived from invasive (biomechanically soft) breast
cancer cells. In particular, we propose multi-parametric AFM structure- mechanical analysis augmented
with machine learning capabilities to further advance label-free, orthogonal biophysical understanding of
EVs beyond biomolecular or particle size characterization and analysis, with significant implications for
research and clinical use of EVs.

25. Development of non-invasive clinically applicable in vivo tracking of extracellular vesicles
using magnetic resonance imaging

1
2
2
2
2
Authors: Johnny Akers , Paola Aguiari , Hasmik Soloyan , Seda Mkhitaryan , Gevorg Karapetyan , Laura
1
2
Perin , Mya Thu , and Sargis Sedrakyan 2
E-mail: jakers@visicellmedical.com
Affiliations:
1 VisiCELL Medical Inc, San Diego, CA, USA.
2 Children’s Hospital Los Angeles/University of Southern California, Los Angeles, CA, USA.
Abstracts: As researchers continue to explore the therapeutic potentials of extracellular vesicles (EVs) for
the treatment of many diseases, there is a growing unmet need for real-time in vivo monitoring of these
therapeutic EVs after they are injected into a subject to understand their safety, targeting, and effectiveness.
While current optical imaging solutions like bioluminescence and fluorescence are useful for EV tracking
studies in animal models, there is limited utility in clinical applications. Here, we present a novel EV
labeling technology that enable real time, non-invasive tracking and quantitative assessment of EVs in
vitro and in vivo utilizing magnetic resonance imaging (MRI). Leveraging clinically applicable magnetic
agents, mesenchymal stem cells-, neural stem cells-, and amniotic fluid stem cells (AFSCs)- derived EVs
were labeled directly or indirectly by labeling the secreting cell first prior to vesicle collection. The magnetic