Search

The aim of this work was a simultaneous analysis of functional platelet activity using both standard optical aggregometry and flow cytometry, by means of measuring P-selectin and GP IIb-IIIa glycoprotein receptor contents on the surface of ADP-induced platelets. GP IIb-IIIa amounts and P-selectin expression on cell surface are significantly increased on platelets after activation with 10 mcM ADP, both in normal donors and in aspirin-treated patients. In clopidogrel-treated patients, the amounts of expressed P-selectin and GP IIb-IIIa did not change after ADP induction, thus suggesting absence of detectable ADP-induced platelet activation in this group. By means of Spearman criterion, a distinct correlation was found between the P-selectin expression, GP IIb-IIIa contents, and rates of standard ADP-induced aggregation. A combination of standard ADP-induced aggregation/activation of platelets with flow cytometry using FITC or PE-labeled antibodies to P-selectin and GP IIb-IIIa, allowed us to apply immunological approaches to analysis of platelet hemostasis, to propose novel laboratory criteria for evaluation of platelet hyperaggregation, and to detect differential effects of clopidogrel and aspirin.

Introduction: We examined the potential role of polymorphisms of the platelet genes GP1BA (rs2243093, rs6065 and VNTR), ITGB3 (rs5918), ITGA2 (rs938043469) and P2RY12 (rs2046934, rs6801273 and rs6798347) as risk factors for myocardial infarction (MI)., Methods: The study population was divided into three groups: controls (n=235), MI at age ≤45 years (MI ≤45, n=44), and MI at age >45 years (MI >45, n=78). The control group was further divided into two subgroups (control ≤45 and >45), and subgroups including only men were also considered for statistical analysis. Polymorphisms were detected by polymerase chain reaction and restriction fragment length polymorphism analysis., Results: Regarding non-genetic risk factors, the control group differed statistically from the MI ≤45 group (p<00.5) in terms of smoking, hypertension, diabetes and obesity, and from the MI >45 group (p<0.05) in terms of hypertension, diabetes, obesity, family history of thrombosis and high cholesterol. For the studied ITGA2 polymorphism, a statistical difference was found when MI >45 was compared with the control group, with a higher risk of MI in the TT genotype (OR 2.852; 95% CI: 1.092-7.451; p=0.032). In the GP1BA rs6065 polymorphism, a statistically significant difference was found between control ≤45 only men and MI ≤45 only men, with a higher risk in the CT genotype (OR 5.568; 95% CI: 1.421-21.822; p=0.016), despite the low numbers included. The other polymorphisms studied did not show any statistically significant correlations., Conclusion: There is a statistically significant association between the TT genotype of the ITGA2 rs938043469 polymorphism and increased risk for MI >45., (Copyright © 2018 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.)