Thromb Haemost 2007; 97(03): 425-434
DOI: 10.1160/TH06-06-0313
Blood Coagulation, Fibrinolysis and Cellular Haemostasis
Schattauer GmbH

Platelet microparticle membranes have 50- to 100-fold higher specific procoagulant activity than activated platelets

Elena I. Sinauridze
1   National Research Center for Hematology, Russian Academy of Medical Sciences, Moscow, Russia
,
Dmitry A. Kireev
1   National Research Center for Hematology, Russian Academy of Medical Sciences, Moscow, Russia
,
Nadezhda Y. Popenko
1   National Research Center for Hematology, Russian Academy of Medical Sciences, Moscow, Russia
,
Aleksei V. Pichugin
2   Institute of Immunology, Ministry of Health, Moscow, Russia
,
Mikhail A. Panteleev
1   National Research Center for Hematology, Russian Academy of Medical Sciences, Moscow, Russia
,
Olga V. Krymskaya
1   National Research Center for Hematology, Russian Academy of Medical Sciences, Moscow, Russia
,
Fazoil I. Ataullakhanov
1   National Research Center for Hematology, Russian Academy of Medical Sciences, Moscow, Russia
3   Faculty of Physics, Moscow State University, Moscow, Russia
4   Center for Theoretical Problems of Physicochemical Pharmacology, Russian Academy of Sciences, Moscow, Russia
› Author Affiliations

Financial support: This study was supported in part by grant 06-04–48426 from the Russian Foundation for Basic Research and by Russian Federation President Grant for Young Candidates of Science MK-7062.2006.4 from the Federal Agency of Science and Innovations.
Further Information

Publication History

Received 07 June 2006

Accepted after resubmission 09 January 2007

Publication Date:
28 November 2017 (online)

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Summary

Platelet microparticles (PMPs) are small vesicles released from blood platelets upon activation. The procoagulant activity of PMPs has been previously mainly characterized by theirability to bind coagulation factors VIII and Va in reconstructed systems. It can be supposed that PMPs can contribute to the development of thrombotic complications in the pathologic states associated with the increase of their blood concentration. In this study we compared procoagulant properties of calcium ionophore A23187-activated platelets and PMPs using several in-vitro models of hemostasis. Surface densities of phosphatidylserine, CD61, CD62P and factor X bound per surface area unit were determined by flow cytometry. They were 2.7-, 8.4-, 4.3-, and 13-fold higher for PMPs than for activated platelets, respectively. Spatial clot growth rate (Vclot) in the reaction-diffus ion experimental model and endogenous thrombin potential (ETP) were determined in plasma, which was depleted of phospholipid cell surfaces by ultra-centrifugation and supplemented with activated platelets or PMPs at different concentrations. Both Vcllot and ETP rapidly increased with the increase of PMP or platelet concentration until saturation was reached. The plateau values of Vclot and ETP for activated platelets and PMPs were similar. In both assays, the procoagulant activity of one PMP was almost equal to that of one activated platelet despite at least two-orders-of-magnitude difference in their surface areas. This suggests that the PMP surface is approximately 50- to 100-fold more procoagulant than the surface of activated platelets.