Extracellular Vesicle Capture by AnTibody of CHoice and Enzymatic Release (EV-CATCHER): A customizable purification assay designed for small-RNA biomarker identification and evaluation of circulating small-EVs

Megan I. Mitchell, Iddo Z. Ben-Dov, Christina Liu, Kenny Ye, Kar Chow, Yael Kramer, Anju Gangadharan, Steven Park, Sean Fitzgerald, Andrew Ramnauth, David S. Perlin, Michele Donato, Emily Bhoy, Ehsan Manouchehri Doulabi, Michael Poulos, Masood Kamali-Moghaddam, Olivier Loudig

Research output: Contribution to journalArticlepeer-review

24 Scopus citations

Abstract

Circulating nucleic acids, encapsulated within small extracellular vesicles (EVs), provide a remote cellular snapshot of biomarkers derived from diseased tissues, however selective isolation is critical. Current laboratory-based purification techniques rely on the physical properties of small-EVs rather than their inherited cellular fingerprints. We established a highly-selective purification assay, termed EV-CATCHER, initially designed for high-throughput analysis of low-abundance small-RNA cargos by next-generation sequencing. We demonstrated its selectivity by specifically isolating and sequencing small-RNAs from mouse small-EVs spiked into human plasma. Western blotting, nanoparticle tracking, and transmission electron microscopy were used to validate and quantify the capture and release of intact small-EVs. As proof-of-principle for sensitive detection of circulating miRNAs, we compared small-RNA sequencing data from a subset of small-EVs serum-purified with EV-CATCHER to data from whole serum, using samples from a small cohort of recently hospitalized Covid-19 patients. We identified and validated, only in small-EVs, hsa-miR-146a and hsa-miR-126-3p to be significantly downregulated with disease severity. Separately, using convalescent sera from recovered Covid-19 patients with high anti-spike IgG titers, we confirmed the neutralizing properties, against SARS-CoV-2 in vitro, of a subset of small-EVs serum-purified by EV-CATCHER, as initially observed with ultracentrifuged small-EVs. Altogether our data highlight the sensitivity and versatility of EV-CATCHER.

Original languageEnglish (US)
Article numbere12110
JournalJournal of Extracellular Vesicles
Volume10
Issue number8
DOIs
StatePublished - Jun 2021

Keywords

  • TEM
  • exosome purification
  • extracellular vesicles
  • micro-RNA profiling
  • sequencing

ASJC Scopus subject areas

  • Histology
  • Cell Biology

Fingerprint

Dive into the research topics of 'Extracellular Vesicle Capture by AnTibody of CHoice and Enzymatic Release (EV-CATCHER): A customizable purification assay designed for small-RNA biomarker identification and evaluation of circulating small-EVs'. Together they form a unique fingerprint.

Cite this