A simple, high-throughput method of protein and label removal from extracellular vesicle samples

Welsh, J. A.; Killingswroth, B.; Kepley, J.; Traynor, T.; McKinnon, K.; Savage, J.; Appel, D.; Aldape, K.; Camphausen, K.; Berzofsky, J. A.; Ivanov, A. R.; Ghiran, I. H.; Jones, J. C.

doi:10.1101/2020.08.20.260307

bioRxiv · 10.1101/2020.08.20.260307

A simple, high-throughput method of protein and label removal from extracellular vesicle samples

Welsh, J. A.·Killingswroth, B.·Kepley, J.·Traynor, T.·McKinnon, K.·Savage, J.·Appel, D.·Aldape, K.·Camphausen, K.·Berzofsky, J. A.·Ivanov, A. R.·Ghiran, I. H.·Jones, J. C.

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Abstract

Evidence continues to increase of the clinical utility extracellular vesicles (EVs) can provide as translational biomarkers. While a wide variety of EV isolation and purification methods have been implemented, few techniques are high-throughput and scalable for removing excess fluorescent reagents (e.g. dyes, antibodies). EVs are too small to be recovered from routine cell-processing procedures, such as filtration or centrifugation. The lack of suitable methods for removing unbound labels, especially in optical assays, is a major roadblock to accurate EV phenotyping and utilization of EV assays in a translational or clinical setting. Therefore, we developed a method for using a multi-modal resin, referred to as EV-Clean, to remove unbound labels from EV samples, and we demonstrate improvement in flow cytometric EV analysis with the use of this EV-Clean method.

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Welsh, J. A., Killingswroth, B., Kepley, J., Traynor, T., McKinnon, K., Savage, J., Appel, D., Aldape, K., Camphausen, K., Berzofsky, J. A., Ivanov, A. R., Ghiran, I. H., Jones, J. C.. 2020-08-21. A simple, high-throughput method of protein and label removal from extracellular vesicle samples. https://doi.org/10.1101/2020.08.20.260307

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