Lytic Resistance of Fibrin Containing Red Blood Cells

作者：Wohner Nikolett; Sotonyi Peter; Machovich Raymund; Szabo Laszlo; Tenekedjiev Kiril; Silva Marta M C G; Longstaff Colin; Kolev Krasimir^*

来源：Arteriosclerosis, Thrombosis, and Vascular Biology, 2011, 31(10): 2306-U343.

DOI：10.1161/ATVBAHA.111.229088

• blood cells
• fibrin
• fibrinolysis
• plasminogen activators
• platelet receptor blockers

Objective-Arterial thrombi contain variable amounts of red blood cells (RBCs), which interact with fibrinogen through an eptifibatide-sensitive receptor and modify the structure of fibrin. In this study, we evaluated the modulator role of RBCs in the lytic susceptibility of fibrin.
Methods and Results-If fibrin is formed at increasing RBC counts, scanning electron microscopy evidenced a decrease in fiber diameter from 150 to 96 nm at 40% (v/v) RBCs, an effect susceptible to eptifibatide inhibition (restoring 140 nm diameter). RBCs prolonged the lysis time in a homogeneous-phase fibrinolytic assay with tissue plasminogen activator (tPA) by up to 22.7 +/- 1.6%, but not in the presence of eptifibatide. Confocal laser microscopy using green fluorescent protein-labeled tPA and orange fluorescent fibrin showed that 20% to 40% (v/v) RBCs significantly slowed down the dissolution of the clots. The fluorescent tPA variant did not accumulate on the surface of fibrin containing RBCs at any cell count above 10%. The presence of RBCs in the clot suppressed the tPA-induced plasminogen activation, resulting in 45% less plasmin generated after 30 minutes of activation at 40% (v/v) RBCs.
Conclusion-RBCs confer lytic resistance to fibrin resulting from modified fibrin structure and impaired plasminogen activation through a mechanism that involves eptifibatide-sensitive fibrinogen-RBC interactions. (Arterioscler Thromb Vasc Biol. 2011;31:2306-2313.)

• 出版日期2011-10
• 单位中国人民解放军海军大连舰艇学院