title: Detection and quantification of microparticles from different cellular lineages using flow cytometry. Evaluation of the impact of secreted phospholipase A2 on microparticle assessment.
abstract: Microparticles, also called microvesicles, are submicron extracellular vesicles produced by plasma membrane budding and shedding recognized as key actors in numerous physio(patho)logical processes. Since they can be released by virtually any cell lineages and are retrieved in biological fluids, microparticles appear as potent biomarkers. However, the small dimensions of microparticles and soluble factors present in body fluids can considerably impede their quantification. Here, flow cytometry with improved methodology for microparticle resolution was used to detect microparticles of human and mouse species generated from platelets, red blood cells, endothelial cells, apoptotic thymocytes and cells from the male reproductive tract. A family of soluble proteins, the secreted phospholipases A2 (sPLA2), comprises enzymes concomitantly expressed with microparticles in biological fluids and that catalyze the hydrolysis of membrane phospholipids. As sPLA2 can hydrolyze phosphatidylserine, a phospholipid frequently used to assess microparticles, and might even clear microparticles, we further considered the impact of relevant sPLA2 enzymes, sPLA2 group IIA, V and X, on microparticle quantification. We observed that if enriched in fluids, certain sPLA2 enzymes impair the quantification of microparticles depending on the species studied, the source of microparticles and the means of detection employed (surface phosphatidylserine or protein antigen detection). This study provides analytical considerations for appropriate interpretation of microparticle cytofluorometric measurements in biological samples containing sPLA2 enzymes.
authors.affiliation: Centre de Recherche en Rhumatologie et Immunologie, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculté de Médecine de l'Université Laval, Québec, QC, Canada.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Rousseau
authors.affiliation: Centre de Recherche du CHUQ and Département d'Obstétrique-Gynécologie, Faculté de Médecine, Université Laval, Québec, QC, Canada.
authors.forename: Clemence
authors.initials: C
authors.lastname: Belleannee
authors.affiliation: Centre de Recherche en Rhumatologie et Immunologie, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculté de Médecine de l'Université Laval, Québec, QC, Canada.
authors.forename: Anne-Claire
authors.initials: AC
authors.lastname: Duchez
authors.affiliation: Centre de Recherche en Rhumatologie et Immunologie, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculté de Médecine de l'Université Laval, Québec, QC, Canada.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Cloutier
authors.affiliation: Centre de Recherche en Rhumatologie et Immunologie, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculté de Médecine de l'Université Laval, Québec, QC, Canada.
authors.forename: Tania
authors.initials: T
authors.lastname: Levesque
authors.affiliation: Centre Hospitalier Universitaire de Québec, Québec, Canada.
authors.forename: Frederic
authors.initials: F
authors.lastname: Jacques
authors.affiliation: Centre Hospitalier Universitaire de Québec, Québec, Canada.
authors.forename: Jean
authors.initials: J
authors.lastname: Perron
authors.affiliation: Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States of America; Division of Immunology, Boston Children's Hospital, Harvard Medical School, Boston, MA, United States of America.
authors.forename: Peter A
authors.initials: PA
authors.lastname: Nigrovic
authors.affiliation: Centre hospitalier de l'Université de Montréal (CRCHUM), Montréal, QC, Canada.
authors.forename: Melanie
authors.initials: M
authors.lastname: Dieude
authors.affiliation: Centre hospitalier de l'Université de Montréal (CRCHUM), Montréal, QC, Canada.
authors.forename: Marie-Josee
authors.initials: MJ
authors.lastname: Hebert
authors.affiliation: Department of Chemistry, University of Washington, Seattle, WA, United States of America.
authors.forename: Michael H
authors.initials: MH
authors.lastname: Gelb
authors.affiliation: Centre de Recherche en Rhumatologie et Immunologie, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculté de Médecine de l'Université Laval, Québec, QC, Canada.
authors.forename: Eric
authors.initials: E
authors.lastname: Boilard
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology; D001792:Blood Platelets / Q000378:metabolism / Q000502:physiology; D019070:Cell Lineage / Q000502:physiology*; D002462:Cell Membrane / Q000378:metabolism / Q000502:physiology; D055252:Cell-Derived Microparticles / Q000378:metabolism* / Q000502:physiology*; D042783:Endothelial Cells / Q000378:metabolism / Q000502:physiology; D004912:Erythrocytes / Q000378:metabolism / Q000502:physiology; D005434:Flow Cytometry / Q000379:methods; D005837:Genitalia, Male / Q000378:metabolism / Q000502:physiology; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D006868:Hydrolysis; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008875:Middle Aged; D054497:Phospholipases A2, Secretory / Q000378:metabolism*; D060168:Thymocytes / Q000378:metabolism / Q000502:physiology
chemical_list: D054497:Phospholipases A2, Secretory