Urinary exosomes are small (<100 nm) vesicles secreted into urine from renal epithelial cells. They are coated with lipid bilayer, they contain an array of membrane and cytosolic proteins, and selected RNA species, reflecting the molecular composition of their cell of origin. Thus, urinary exosomes have received considerable attention as potential biomarker source, as their proteomic analysis could lead to the discovery of new non-invasive site-specific biomarkers for renal diseases. Here, researchers from the University of Milano-Bicocca describe a robust method for urinary exosome preparation, additional protocols for their biochemical characterization and for the quantitation of different preparations, to be used for comparative proteomic studies.
Preparation of urinary exosomes
Pitto M, Corbetta S, Raimondo F. (2015) Preparation of urinary exosomes: methodological issues for clinical proteomics. Methods Mol Biol 1243:43-53. [abstract]