title: A comprehensive characterization of membrane vesicles released by autophagic human endothelial cells.
abstract: The stress status of the apoptotic cell can promote phenotypic changes that have important consequences on the immunogenicity of the dying cell. Autophagy is one of the biological processes activated in response to a stressful condition. It is an important mediator of intercellular communications, both by regulating the unconventional secretion of molecules, including interleukin 1β, and by regulating the extracellular release of ATP from early stage apoptotic cells. Additionally, autophagic components can be released in a caspase-dependent manner by serum-starved human endothelial cells that have engaged apoptotic and autophagic processes. The nature and the components of the extracellular vesicles released by dying autophagic cells are not known. In this study, we have identified extracellular membrane vesicles that are released by human endothelial cells undergoing apoptosis and autophagy, and characterized their biochemical, ultrastructural, morphological properties as well as their proteome. These extracellular vesicles differ from classical apoptotic bodies because they do not contain nucleus components and are released independently of Rho-associated, coiled-coil containing protein kinase 1 activation. Instead, they are enriched with autophagosomes and mitochondria and convey various danger signals, including ATP, suggesting that they could be involved in the modulation of innate immunity.
authors: Research Centre, Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Canada.
authors: Nicolas
authors: N
authors: Pallet
authors: Isabelle
authors: I
authors: Sirois
authors: Christina
authors: C
authors: Bell
authors: Laïla-Aïcha
authors: LA
authors: Hanafi
authors: Katia
authors: K
authors: Hamelin
authors: Mélanie
authors: M
authors: Dieudé
authors: Christiane
authors: C
authors: Rondeau
authors: Pierre
authors: P
authors: Thibault
authors: Michel
authors: M
authors: Desjardins
authors: Marie-Josée
authors: MJ
authors: Hebert
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D001343:Autophagy / Q000187:drug effects; D016895:Culture Media, Serum-Free / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D055354:Exosomes / Q000378:metabolism* / Q000648:ultrastructure; D061307:Human Umbilical Vein Endothelial Cells / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D006801:Humans; D009336:Necrosis; D010588:Phagosomes / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D040901:Proteomics; D054460:rho-Associated Kinases / Q000378:metabolism
chemical_list: D016895:Culture Media, Serum-Free; D054460:rho-Associated Kinases