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PubMed · 16479606

High density lipoprotein modulates platelet function.

Stefan Barlage·Dorothee Boettcher·Alfred Boettcher·Ashraf Dada·Gerd Schmitz
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Abstract

BACKGROUND: Platelet activation by atherogenic lipoproteins can be antagonized by high density lipoprotein (HDL), probably via interaction with the ATP-binding cassette transporter A1 (ABCA1). METHODS: ABCA1 expression and its association with cholesterol rich membrane domains was analyzed by mRNA and Western blot analysis. HDL effects on platelet receptor clustering were analyzed by flow cytometric analysis of fluorescence resonance energy transfer between fluorochrome-labeled antibodies. RESULTS: ABCA1 expression increased upon megakaryocytic differentiation of human stem cells and ABCA1 protein partially associated to LubroIWX-resistant membrane domains. Plasma HDL-cholesterol in healthy donors negatively correlated to the platelet membrane cholesterol content. Receptor cluster analysis revealed a decrease in the association of Gplb and FcgammaRII upon incubation of platelets with HDL3. CONCLUSION: Our results suggest that HDL modulates platelet reactivity by altering lipid raft associated receptor clustering.

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ATP Binding Cassette Transporter 1ATP-Binding Cassette TransportersAntigens, CD34Blood PlateletsBlotting, WesternCell DifferentiationFetal BloodFlow CytometryFluorescence Resonance Energy TransferGene ExpressionHumansIntegrin beta3Lipoproteins, HDLLipoproteins, HDL3MegakaryocytesMembrane GlycoproteinsMembrane MicrodomainsMembrane ProteinsPlatelet Glycoprotein GPIb-IX ComplexPlatelet Membrane Glycoprotein IIbProtein BindingRNA, MessengerReceptors, IgGStem CellsJournal Article

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Stefan Barlage, Dorothee Boettcher, Alfred Boettcher, Ashraf Dada, Gerd Schmitz. 2006. High density lipoprotein modulates platelet function.. https://doi.org/10.1002/cyto.a.20214

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