title: Dynamic microvesicle release and clearance within the cardiovascular system: triggers and mechanisms.
abstract: Interest in cell-derived microvesicles (or microparticles) within cardiovascular diagnostics and therapeutics is rapidly growing. Microvesicles are often measured in the circulation at a single time point. However, it is becoming clear that microvesicle levels both increase and decrease rapidly in response to certain stimuli such as hypoxia, acute cardiac stress, shear stress, hypertriglyceridaemia and inflammation. Consequently, the levels of circulating microvesicles will reflect the balance between dynamic mechanisms for release and clearance. The present review describes the range of triggers currently known to lead to microvesicle release from different cellular origins into the circulation. Specifically, the published data are used to summarize the dynamic impact of these triggers on the degree and rate of microvesicle release. Secondly, a summary of the current understanding of microvesicle clearance via different cellular systems, including the endothelial cell and macrophage, is presented, based on reported studies of clearance in experimental models and clinical scenarios, such as transfusion or cardiac stress. Together, this information can be used to provide insights into potential underlying biological mechanisms that might explain the increases or decreases in circulating microvesicle levels that have been reported and help to design future clinical studies.
authors.affiliation: Oxford Cardiovascular Clinical Research Facility, University of Oxford, Oxford OX3 9DU, U.K. Department of Clinical and Laboratory Immunology, Oxford University Hospitals NHS Trust, Oxford OX3 7LE, U.K. lisa.ayers@nhs.net.
authors.forename: Lisa
authors.initials: L
authors.lastname: Ayers
authors.affiliation: Academic Medical Centre, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands.
authors.forename: Rienk
authors.initials: R
authors.lastname: Nieuwland
authors.affiliation: Department of Pulmonology, University Hospital of Zurich, and University of Zurich, 8091 Zurich, Switzerland.
authors.forename: Malcolm
authors.initials: M
authors.lastname: Kohler
authors.affiliation: Division of Cardiology, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, 10117 Berlin, Germany.
authors.forename: Nicolle
authors.initials: N
authors.lastname: Kraenkel
authors.affiliation: Department of Clinical and Laboratory Immunology, Oxford University Hospitals NHS Trust, Oxford OX3 7LE, U.K.
authors.forename: Berne
authors.initials: B
authors.lastname: Ferry
authors.affiliation: Oxford Cardiovascular Clinical Research Facility, University of Oxford, Oxford OX3 9DU, U.K.
authors.forename: Paul
authors.initials: P
authors.lastname: Leeson
mesh_terms: D000818:Animals; D002318:Cardiovascular Diseases / Q000378:metabolism / Q000473:pathology* / Q000503:physiopathology; D002319:Cardiovascular System / Q000378:metabolism / Q000473:pathology* / Q000503:physiopathology; D055252:Cell-Derived Microparticles / Q000378:metabolism / Q000473:pathology*; D004734:Energy Metabolism; D005786:Gene Expression Regulation; D006801:Humans; D018836:Inflammation Mediators / Q000378:metabolism; D007700:Kinetics; D011379:Prognosis; D012307:Risk Factors; D015398:Signal Transduction
chemical_list: D018836:Inflammation Mediators
keywords: cardiovascular disease; clinical studies; microparticles; microvesicles