A Nanoparticle-Based Approach for the Detection of Extracellular Vesicles

Sci Rep. 2019 Jul 11;9(1):10038. doi: 10.1038/s41598-019-46395-2.

Abstract

The analysis of extracellular vesicles (EVs) typically requires tedious and time-consuming isolation process from bio-fluids. We developed a nanoparticle-based time resolved fluorescence immunoassay (NP-TRFIA) that uses biotinylated antibodies against the proteins of tetraspanin family and tumor-associated antigens for capturing EVs from urine samples and cell culture supernatants without the need for isolation. The captured-EVs were detected either with Eu3+-chelate or Eu3+-doped nanoparticle-based labels conjugated either to antibodies against the tetraspanins or lectins targeting the glycan moieties on EVs surface. The NP-TRFIA demonstrated specific capturing and detection of EVs by antibodies and lectins. Lectin-nanoparticle based assays showed 2-10 fold higher signal-to-background ratio compared with lectin-chelate assays. The nanoparticle assay concept allowed surface glycosylation profiling of the urine derived-EVs with lectins. It was also applied to establish an assay showing differential expression of tumor-associated proteins on more aggressive (higher ITGA3 on DU145- and PC3-EVs) compared to less aggressive (higher EpCAM on LNCaP-EVs) PCa- cell lines derived-EVs. This NP-TRFIA can be used as a simple tool for analysis and characterization of EVs in urine and cell culture supernatants. Such approach could be useful in identification of disease-specific markers on the surface of patient-derived urinary EVs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Antibodies / immunology
  • Biomarkers / analysis
  • Cell Line, Tumor
  • Extracellular Vesicles / metabolism*
  • Female
  • Glycoproteins / analysis*
  • Glycoproteins / immunology
  • Glycosylation
  • Humans
  • Immunoassay / methods*
  • Lectins / metabolism
  • Male
  • Nanoparticles / chemistry*
  • Prostatic Neoplasms / diagnosis
  • Tetraspanins / analysis*
  • Tetraspanins / immunology
  • Urine / chemistry

Substances

  • Antibodies
  • Biomarkers
  • Glycoproteins
  • Lectins
  • Tetraspanins