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Determination of the Procoagulant Activity of Extracellular Vesicle (EV) Using EV-Activated Clotting Time (EV-ACT)
Published on: August 4, 2023
Increased procoagulant cell-derived microparticles (C-MP) in splenectomized patients with ITP.
1Wallace H Coulter Platelet Laboratory, Division of Hematology/Oncology, University of Miami, Miller School of Medicine, 1600 NW 10th Ave, Room 7109A, Miami, FL 33136, USA.
Thrombosis Research
|March 13, 2008
Summary
Splenectomy increases cell-derived microparticles (C-MP), particularly red cell-derived (RMP) and leukocyte-derived (LMP), potentially raising thrombosis and cardiovascular disease risks. The spleen likely clears these procoagulant C-MP.
Area of Science:
- Hematology
- Immunology
- Vascular Biology
Background:
- Splenectomy is a common procedure with incompletely understood long-term safety.
- While infection risk is known, thrombosis and cardiovascular disease risks post-splenectomy require further elucidation.
Purpose of the Study:
- To investigate levels of cell-derived microparticles (C-MP) in splenectomized versus non-splenectomized patients with immune thrombocytopenia (ITP).
- To explore the association between C-MP levels, coagulation parameters, and potential long-term risks following splenectomy.
Main Methods:
- Assessed levels of platelet-derived (PMP), leukocyte-derived (LMP), red cell-derived (RMP), and endothelial cell-derived (EMP) microparticles via flow cytometry.
- Measured coagulation parameters including PT, aPTT, and FVIII, IX, XI activities.
- Compared these measures between 23 splenectomized ITP (ITP-S) and 53 non-splenectomized ITP (ITP-nS) patients.
Main Results:
- Significantly elevated RMP (p=0.0035) and LMP (p<0.0001) were observed in ITP-S patients compared to ITP-nS.
- ITP-S patients exhibited significantly shorter aPTT (p=0.029).
- RMP correlated with shorter aPTT and increased activities of factors VIII, IX, and XI.
Conclusions:
- Splenectomy is associated with elevated RMP and LMP, suggesting the spleen's role in clearing procoagulant C-MP.
- Increased C-MP levels post-splenectomy may contribute to heightened risks of thrombosis, atherosclerosis, and cardiovascular disease.
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