Elevated levels of thrombin‐generating microparticles in stored red blood cells. Issue 1 (25th January 2013)

• Record Type: Journal Article
• Authors: Gao, Y.; Lv, L.; Liu, S.; Ma, G.; Su, Y.
• Is Part Of: Vox sanguinis. Volume 105:Issue 1(2013)
• Page Start: 11
• Page End: 17
• Publication Date: 2013-01-25
• Subjects: Blood -- Periodicals; Blood -- Transfusion -- Periodicals; Immunohematology -- Periodicals; Immunopathology -- Periodicals; 615.39
• DOI: 10.1111/vox.12014
• Languages: English
• ISSNs: 0042-9007

Abstract

<abstract abstract-type="main" xml:lang="en" id="vox12014-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="vox12014-sec-0001" sec-type="section"> <title>Background</title> <p>During storage, red blood cells (RBCs) lose their membrane stability, leading to haemolysis and microparticle (MP) formation. The use of RBCs stored for more than 28 days has been associated with an increased incidence of deep vein thrombosis. However, the exact mechanism by which coagulation activation is enhanced in stored RBCs is still unknown.</p> </sec> <sec id="vox12014-sec-0002" sec-type="section"> <title>Objectives</title> <p>To investigate the relevant potential procoagulant activities of MPs and study the relative procoagulant factors for initiating the coagulation on MPs in stored RBCs.</p> </sec> <sec id="vox12014-sec-0003" sec-type="section"> <title>Study Design and Methods</title> <p>MPs were isolated from the plasma of RBC units stored in citrate–phosphate–dextrose–adenine. At seven storage time‐points (d0, d7, d14, d21, d28, d35 and d42), MPs were morphologically observed, quantified and analysed for tissue factor, factor XI (FXI) and their thrombin‐generating potential.</p> </sec> <sec id="vox12014-sec-0004" sec-type="section"> <title>Results</title> <p>MPs were observed using electron microscopy. The size of the MPs ranged from 0·272 μm to 0·973 μm in diameter. During the storage of RBCs in plastic bags, the MP concentration increased from 3389 ± 218/μl at day 0 to 61 586 ± 2237/μl at d42. Thrombin generation was dependent on the total number of MPs (<italic>r</italic> = 0·987). Anti‐human FXI antibody inhibited thrombin concentrations by 50·3% compared with control plasma, whereas antitissue factor and antitissue factor pathway inhibitor failed to reduce thrombin concentrations.</p> </sec> <sec id="vox12014-sec-0005" sec-type="section"> <title>Conclusions</title> <p>Our study provides evidence that MP formation due to RBC storage might propagate coagulation not only by exposing phosphatidylserine, but also by initiating thrombin generation independently of tissue factor in a FXI ‐dependent manner.</p> </sec> </abstract>