Phosphatidylserine-exposing blood and endothelial cells contribute to the hypercoagulable state in essential thrombocythemia patients
Phosphatidylserine-exposing blood and endothelial cells contribute to the hypercoagulable state in essential thrombocythemia patients
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暴露于磷脂酰丝氨酸的血液和内皮细胞导致原发性血小板增多症患者的高凝状态。
DOI：
10.1007/s00277-018-3228-6
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发表时间：
2018-04-01
影响因子：
3.5
通讯作者：
Shi, Jialan
中科院分区：
文献类型：
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作者：
Tong, Dongxia;Yu, Muxin;Shi, Jialan
原发性血小板增多症（ET）的血栓形成机制复杂且尚未明确。我们的目的是探讨血细胞和内皮细胞（ECs）上磷脂酰丝氨酸（PS）的暴露是否可以解释ET突变亚型中血栓形成增加以及不同的血栓风险。通过流式细胞术和共聚焦显微镜，我们发现每个ET组（JAK2、CALR和三阴性（TN），所有P < 0.001）中暴露PS的红细胞、血小板、白细胞以及血清培养的内皮细胞水平均显著高于对照组。在ET患者中，JAK2突变患者的PS阳性红细胞、血小板、中性粒细胞以及血清培养的内皮细胞水平高于TN患者或CALR突变患者，后两者水平相似。凝血功能检测表明，较高水平的PS阳性血细胞和血清培养的内皮细胞导致凝血时间显著缩短，以及FXa、凝血酶和纤维蛋白生成水平大幅增加。这种促凝血活性可通过添加乳黏素在很大程度上被阻断（约70%抑制）。共聚焦显微镜显示，FVa/FXa复合物和纤维蛋白原纤维与ET血清培养的内皮细胞上的PS共定位。此外，我们发现D - 二聚体、凝血酶原片段F1 + 2与PS暴露之间存在关联。我们的研究揭示了高凝状态与细胞上暴露的PS之间先前未被认识的联系，这可能也与ET突变亚型中不同的血栓风险有关。因此，阻断PS结合位点可能代表一种预防ET血栓形成的新治疗靶点。
The mechanisms of thrombogenicity in essential thrombocythemia (ET) are complex and not well defined. Our objective was to explore whether phosphatidylserine (PS) exposure on blood cells and endothelial cells (ECs) can account for the increased thrombosis and distinct thrombotic risks among mutational subtypes in ET. Using flow cytometry and confocal microscopy, we found that the levels of PS-exposing erythrocytes, platelets, leukocytes, and serum-cultured ECs were significantly higher in each ET group [JAK2, CALR, and triple-negative (TN) (all P < 0.001)] than those in controls. Among ET patients, those with JAK2 mutations showed higher levels of PS-positive erythrocytes, platelets, neutrophils, and serum-cultured ECs than TN patients or those with CALR mutations, which show similar levels. Coagulation function assays showed that higher levels of PS-positive blood cells and serum-cultured ECs led to markedly shortened coagulation time and dramatically increased levels of FXa, thrombin, and fibrin production. This procoagulant activity could be largely blocked by addition of lactadherin (approx. 70% inhibition). Confocal microscopy showed that the FVa/FXa complex and fibrin fibrils colocalized with PS on ET serum-cultured ECs. Additionally, we found a relationship between D-dimer, prothrombin fragment F1 + 2, and PS exposure. Our study reveals a previously unrecognized link between hypercoagulability and exposed PS on cells, which might also be associated with distinct thrombotic risks among mutational subtypes in ET. Thus, blocking PS-binding sites may represent a new therapeutic target for preventing thrombosis in ET.