BACKGROUND: Microparticles (MPs) are small (0.1-1 μm) cell-derived vesicles released during activation or apoptosis, with a surface-exposed phosphatidylserine along with antigens indicating the cellular origin. The level of MPs is known to be elevated in thromboembolic diseases and malignancies; it is believed that MPs are not only amplifying but can also initiate the thrombogenesis processes. BCR/ABL negative myeloproliferative neoplasms (MPNs) are clonal haematopoietic diseases, which include polycythemia vera, essential thrombocythemia and primary myelofibrosis. One of the main problems of MPN patients is high risk and incidence of thrombosis which affect the survival, quality of life and life expectancy. PATIENTS AND METHODS: The clinical significance of circulating MPs was assessed in a group of 179 patients with BCR/ABL-negative MPNs. Analysis of MPs was done using flow cytometry on 417 samples, and MPs procoagulation activity was performed using a functional assay called Zymuphen MP-activity (Hyphen Biomed, Neuville-sur-oise, France) on 274 samples. RESULTS: Significantly higher absolute and relative count of platelet MPs was found in MPN patients when compared with healthy group, respectively (p = 0.001, p = 0.043). Erythrocyte MPs were also significantly higher in MPN patients than in the healthy group (p < 0.001). Procoagulation activity of MPs was as well significantly higher in patients compared to the control group (p < 0.001). Patients with primary myelofibrosis had decreased absolute and relative count of platelet MPs compared to polycythemia vera and essential thrombocythemia patients, respectively (p = 0.008, p = 0.014). Presence of JAK2V617F mutation was associated with higher absolute and relative count of platelet MPs, respectively (p = 0.045, p = 0.029). CONCLUSION: Although some literature data support the hypothesis of a direct relation between MPs and thrombotic events in MPN patients, further studies are needed to evaluate the clinical implication of MPs in the hypercoagulation state of MPN patients.
- Klíčová slova
- Janus Kinase 2, microparticles, myeloproliferative disorders, procoagulation activity, thrombosis,
- MeSH
- bcr-abl fúzové proteiny genetika MeSH
- dospělí MeSH
- kvalita života * MeSH
- lidé středního věku MeSH
- lidé MeSH
- mikropartikule metabolismus patologie MeSH
- myeloproliferativní poruchy komplikace genetika MeSH
- nádorové biomarkery krev MeSH
- následné studie MeSH
- pilotní projekty MeSH
- studie případů a kontrol MeSH
- trombóza krev diagnóza etiologie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- bcr-abl fúzové proteiny MeSH
- nádorové biomarkery MeSH
Microparticles are small membrane fragments with dimension between 0.1 and 1 μm, which are released during cell activation or apoptosis, exposing the phospholipid phosphatidylserine and membrane antigens typical for cellular origin. Philadelphia-negative myeloproliferative neoplasms (MPNs) are characterized by an increased risk of thrombosis. Data from literature suggest an association between thrombosis and the procoagulant activity of microparticles. Association between the procoagulant activity of microparticles and the incidence of thrombosis was assesed in a group of 126 patients with Philadelphia-negative MPNs. Measurement of microparticles procoagulant activity was performed using a functional assay, namely the Zymuphen MP-activity (Hyphen Biomed, Neuville-sur-oise, France). A total of 539 samples were analysed within this group of patients, regardless of patients' state of health. A significantly higher circulating microparticles procoagulant activity was found in MPN patients as compared with the control group (P < 0.001). A pathological level of procoagulant activity was observed more frequently in patients with polycythaemia vera (88%, P = 0.002) than groups of patients with essential thrombocythaemia (73.2%) and primary myelofibrosis (68.3%); the same result was confirmed in patients with a history of venous thrombosis in comparison with patients without thrombosis (84.7 vs. 73.2%, P = 0.029). Patients without cytoreductive treatment had a higher activity of microparticles (P = 0.010). Furthermore, presence of JAK2 V617F mutation was associated with an increased procoagulant activity (P = 0.007), as well as the higher JAK2 V617F allele burden (P = 0.001). Further prospective clinical studies will be necessary to evaluate the clinical relevance of microparticles in the prediction hypercoagulable state in these patients.
- MeSH
- incidence MeSH
- lidé středního věku MeSH
- lidé MeSH
- mikropartikule patologie MeSH
- myeloproliferativní poruchy krev komplikace patologie MeSH
- polycythaemia vera krev komplikace patologie MeSH
- trombóza krev etiologie patologie MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
OBJECTIVES: Recent technological breakthroughs in the design of reliable systems for long term non-pulsatile mechanical heart support offer the possibility to study the effect of continuous blood flow in the vascular system. Generally, it is assumed that the absence of physiological pulsatile flow leads to prothrombogenic and proatherogenic changes. We investigated the change in the circulating endothelial microparticle concentration as a marker of endothelial damage in patients implanted with a continuous-flow left ventricle assist device (LVAD). METHODS: Endothelial microparticles were measured in 8 males (mean age 54.1±11.5 years) with terminal heart failure before and 3 months after implantation of an LVAD. The group consisted of 3 patients with dilated cardiomyopathy, 3 patients with ischemic cardiomyopathy, 1 patient with both conditions and 1 patient with congenital valvular disease. The concentration of endothelial microparticles was determined by ELISA Zymutest MP activity test. RESULTS: We did not observe a significant change in the concentration of circulating endothelial microparticles measured before and 3 months after implantation (p=0.669). High inter-individual variability in response to implantation was found. However, no association between a change in endothelial microparticle concentration and heart failure aetiology or a significant clinical complication attributed to LVAD implantation was observed. CONCLUSION: Results from this preliminary pilot study do not indicate that LVADs contribute to short-term vascular damage as defined by an increase in circulating endothelial microparticles.
- MeSH
- biologické markery krev MeSH
- cévní endotel metabolismus patologie MeSH
- dilatační kardiomyopatie krev chirurgie MeSH
- dospělí MeSH
- hemodynamika fyziologie MeSH
- ischemická choroba srdeční krev chirurgie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mikropartikule metabolismus patologie MeSH
- pilotní projekty MeSH
- podpůrné srdeční systémy škodlivé účinky MeSH
- prospektivní studie MeSH
- senioři MeSH
- srdeční selhání krev chirurgie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- Publikační typ
- časopisecké články MeSH
- klinické zkoušky MeSH
- práce podpořená grantem MeSH
- Názvy látek
- biologické markery MeSH
