Characterization of RNA from Exosomes and Other Extracellular Vesicles Isolated by a Novel Spin Column-Based Method

PLoS One. 2015 Aug 28;10(8):e0136133. doi: 10.1371/journal.pone.0136133. eCollection 2015.

Abstract

Exosomes and other extracellular vesicles (commonly referred to as EVs) have generated a lot of attention for their potential applications in both diagnostics and therapeutics. The contents of these vesicles are the subject of intense research, and the relatively recent discovery of RNA inside EVs has raised interest in the biological function of these RNAs as well as their potential as biomarkers for cancer and other diseases. Traditional ultracentrifugation-based protocols to isolate EVs are labor-intensive and subject to significant variability. Various attempts to develop methods with robust, reproducible performance have not yet been completely successful. Here, we report the development and characterization of a spin column-based method for the isolation of total RNA from EVs in serum and plasma. This method isolates highly pure RNA of equal or higher quantity compared to ultracentrifugation, with high specificity for vesicular over non-vesicular RNA. The spin columns have a capacity to handle up to 4 mL sample volume, enabling detection of low-abundance transcripts in serum and plasma. We conclude that the method is an improvement over traditional methods in providing a faster, more standardized way to achieve reliable high quality RNA preparations from EVs in biofluids such as serum and plasma. The first kit utilizing this new method has recently been made available by Qiagen as "exoRNeasy Serum/Plasma Maxi Kit".

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell-Derived Microparticles / chemistry*
  • Cell-Derived Microparticles / metabolism
  • Exosomes / chemistry*
  • Exosomes / metabolism
  • Female
  • Humans
  • Male
  • RNA / blood
  • RNA / isolation & purification*
  • Reagent Kits, Diagnostic
  • Ultracentrifugation / methods

Substances

  • Reagent Kits, Diagnostic
  • RNA

Grant support

This work was partly supported by a grant from the M4 Spitzencluster Initiative of the German Bundesministerium für Bildung und Forschung (BMBF) with the Förderkennzeichen FKD:16EX1121D. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. There were no additional funding sources for this study. Exosome Diagnostics and QIAGEN provided support in the form of salaries for authors DE, AS, CC, EB, RM, MS, MSH, JMS, EL, JS, MN, but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of these authors are articulated in the ‘author contributions’ section.