Framework for rapid comparison of extracellular vesicle isolation methods
- Wyss Institute for Biologically Inspired Engineering, United States
Abstract
Extracellular vesicles (EVs) are released by all cells into biofluids and hold great promise as reservoirs of disease biomarkers. One of the main challenges in studying EVs is a lack of methods to quantify EVs that are sensitive enough and can differentiate EVs from similarly sized lipoproteins and protein aggregates. We demonstrate the use of ultrasensitive, single molecule array (Simoa) assays for the quantification of EVs using three widely expressed transmembrane proteins: the tetraspanins CD9, CD63, and CD81. Using Simoa to measure these three EV markers, as well as albumin to measure protein contamination, we were able to compare the relative efficiency and purity of several commonly used EV isolation methods in plasma and cerebrospinal fluid (CSF): ultracentrifugation, precipitation, and size exclusion chromatography (SEC). We further used these assays, all on one platform, to improve SEC isolation from plasma and CSF. Our results highlight the utility of quantifying EV proteins using Simoa and provide a rapid framework for comparing and improving EV isolation methods from biofluids.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Dmitry Ter-Ovanesyan
Funding
Chan Zuckerberg Initiative (NDCN Collaborative Science Award)
- Dmitry Ter-Ovanesyan
- Maia Norman
- Roey Lazarovits
- Wendy Trieu
- Ju-Hyun Lee
- George Church
- David R Walt
Open Philanthropy Project
- Dmitry Ter-Ovanesyan
- Maia Norman
- Roey Lazarovits
- Wendy Trieu
- Ju-Hyun Lee
- David R Walt
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Ter-Ovanesyan et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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