title: Small platelet microparticle levels are increased in pulmonary arterial hypertension.
abstract: BACKGROUND
  The various aetiologies and risk factors for pulmonary arterial hypertension (PAH) lead to close phenotypes with small differences. Plasma microparticles have been shown to be increased in vascular pathologies including PAH. The aim of this study was to determine whether the levels of endothelial and platelet-derived microparticles could vary between different forms of PAH: idiopathic PAH (iPAH), heritable PAH associated with BMPR2 (Bone morphogenetic protein receptor, type II) mutation (hPAH) and PAH associated with connective tissue diseases (aPAH).
  
  
  METHODS
  Microparticles were analysed using flow cytometry in plasma from controls and iPAH, hPAH and aPAH patients. Platelet-derived MP (PMP) were defined as CD31(+)/CD41(+) and endothelial-derived MP (EMP) as CD31(+)/CD41(-). Two populations of PMP were isolated according to their size, defining small PMP (0·3-0·5 μm) and large PMP (0·5-0·9 μm). BMPR2 genotype, clinical and biologic parameters were recorded.
  
  
  RESULTS
  EMP and small PMP levels in iPAH, hPAH and aPAH were similar and were significantly increased as compared with controls. No differences in large PMP levels were observed. After adjusting for age, sex, proBNP and CRP, EMP and small PMP levels did not correlate with clinical parameters.
  
  
  CONCLUSIONS
  iPAH, hPAH and aPAH were characterized by increased levels of EMP and of small PMP, a new class of PMP which seems to be differentially produced than large PMP.
authors.affiliation: INSERM UMR_S 956, Paris, France.
authors.forename: Sophie
authors.initials: S
authors.lastname: Nadaud
authors.forename: Odette
authors.initials: O
authors.lastname: Poirier
authors.forename: Barbara
authors.initials: B
authors.lastname: Girerd
authors.forename: Catherine
authors.initials: C
authors.lastname: Blanc
authors.forename: David
authors.initials: D
authors.lastname: Montani
authors.forename: Mélanie
authors.initials: M
authors.lastname: Eyries
authors.forename: Françoise
authors.initials: F
authors.lastname: Imbert-Bismut
authors.forename: Antoine
authors.initials: A
authors.lastname: Pacheco
authors.forename: Jacques
authors.initials: J
authors.lastname: Vigne
authors.forename: David-Alexandre
authors.initials: DA
authors.lastname: Tregouet
authors.forename: Marc
authors.initials: M
authors.lastname: Humbert
authors.forename: Florent
authors.initials: F
authors.lastname: Soubrier
mesh_terms: D000328:Adult; D000368:Aged; D001792:Blood Platelets / Q000166:cytology*; D052006:Bone Morphogenetic Protein Receptors, Type II / Q000032:analysis*; D016022:Case-Control Studies; D055252:Cell-Derived Microparticles / Q000145:classification / Q000378:metabolism*; D042783:Endothelial Cells / Q000166:cytology*; D005260:Female; D005434:Flow Cytometry; D005838:Genotype; D006801:Humans; D006976:Hypertension, Pulmonary / Q000097:blood* / Q000145:classification / Q000235:genetics; D016014:Linear Models; D008297:Male; D008875:Middle Aged
chemical_list: D052006:Bone Morphogenetic Protein Receptors, Type II