title: Size-dependent cellular uptake of exosomes.
abstract: The ability of exosomes to elicit specific cellular responses suggests that they may be increasingly used as therapeutics. Their vesicular nature makes them suitable as potential nanocarriers for drugs or nucleic acids delivery. Here we address the question whether the method of preparation of enriched exosomal fractions can affect their uptake by cells and their ability to trigger a response. We compared ultracentrifugation and polymer-based precipitation methods on supernatants of glioma-associated stem cells isolated from a high-grade glioma patient. We determined particle size distributions after purification and their correlation with uptake, proliferation and migration in glioblastoma cell cultures. Our findings indicate that polymer-based precipitation leads to smaller particle size distributions, faster uptake by target cells and increased cellular motility. The different effect that isolation method-dependent populations of particles have on cell motility suggests their size distribution could also profoundly affect exosomes therapeutic potential.
authors.affiliation: School of Life Sciences, University of Lincoln, Lincoln, UK; Department of Medical and Biological Sciences, University of Udine, Udine, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Caponnetto
authors.affiliation: Department of Medical and Biological Sciences, University of Udine, Udine, Italy.
authors.forename: Ivana
authors.initials: I
authors.lastname: Manini
authors.affiliation: Neurosurgery Unit, Department of Neuroscience, Santa Maria della Misericordia University Hospital, Udine, Italy.
authors.forename: Miran
authors.initials: M
authors.lastname: Skrap
authors.affiliation: School of Life Sciences, University of Lincoln, Lincoln, UK.
authors.forename: Timea
authors.initials: T
authors.lastname: Palmai-Pallag
authors.affiliation: Department of Medical and Biological Sciences, University of Udine, Udine, Italy.
authors.forename: Carla
authors.initials: C
authors.lastname: Di Loreto
authors.affiliation: Department of Medical and Biological Sciences, University of Udine, Udine, Italy.
authors.forename: Antonio Paolo
authors.initials: AP
authors.lastname: Beltrami
authors.affiliation: Department of Medical and Biological Sciences, University of Udine, Udine, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Cesselli
authors.affiliation: School of Life Sciences, University of Lincoln, Lincoln, UK. Electronic address: eferrari@lincoln.ac.uk.
authors.forename: Enrico
authors.initials: E
authors.lastname: Ferrari
mesh_terms: D002458:Cell Fractionation; D045744:Cell Line, Tumor; D002465:Cell Movement; D049109:Cell Proliferation; D011232:Chemical Precipitation; D055354:Exosomes / Q000378:metabolism* / Q000473:pathology / Q000648:ultrastructure; D005434:Flow Cytometry; D005910:Glioma / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D014407:Tumor Cells, Cultured; D014461:Ultracentrifugation
keywords: AFM; Cellular uptake; Exosomes; Flow cytometry; GASC; Glioma