Wehmeier A, Tschöpe D, Esser J, Menzel C, Nieuwenhuis H K, Schneider W
Department of Haematology, Oncology and Clinical Immunology, Heinrich-Heine University, Düsseldorf, FRG.
Thromb Res. 1991 Feb 1;61(3):271-8. doi: 10.1016/0049-3848(91)90103-4.
Platelet activation in patients with myeloproliferative disorders is often suggested by increased platelet alpha-granule secretion and an acquired storage pool defect of dense granules. To determine whether activated platelets circulate in patients with chronic myeloproliferative disorders, we evaluated the binding of monoclonal antibodies against activation-dependent epitopes on resting platelets (P 12, CD 63, and CD 62) in 12 patients with prominent megakaryocytic proliferation (8 patients with essential thrombocythemia, 2 with chronic myeloid leukemia, and 2 patients with polycythemia rubra vera). In addition, platelet aggregation in response to collagen, adenosine diphosphate, platelet activating factor, and agglutination with ristocetin was investigated. In 3 patients there was an increased percentage of platelets binding at least 1 activation marker. In 2 other patients, a trend towards increased antibody binding was observed. Binding of the antibody to thrombospondin (P 12) was related to expression of the GMP 140 protein (CD 62, r = 0.76, p = 0.004). There was no correlation of platelet aggregation defects in vitro to increased expression of platelet activation markers or to thrombohaemorrhagic complications. However, circulating activated platelets were detected in three out of five patients with a history of bleeding or thrombotic complications. The results of this preliminary study suggest that some but not all patients with myeloproliferative disorders showed increased amounts of circulating activated platelets. The relation of bleeding and thrombotic complications to the expression of activation-dependent epitopes on platelets in myeloproliferative disorders requires further investigation.
骨髓增殖性疾病患者的血小板活化通常表现为血小板α-颗粒分泌增加以及致密颗粒的获得性储存池缺陷。为了确定慢性骨髓增殖性疾病患者体内是否存在循环活化血小板，我们评估了12例巨核细胞显著增殖患者（8例原发性血小板增多症患者、2例慢性髓性白血病患者和2例真性红细胞增多症患者）静息血小板上与活化依赖性表位结合的单克隆抗体（P12、CD63和CD62）的结合情况。此外，还研究了血小板对胶原、二磷酸腺苷、血小板活化因子的聚集反应以及与瑞斯托霉素的凝集反应。3例患者中，至少结合1种活化标志物的血小板百分比增加。另外2例患者观察到抗体结合有增加的趋势。抗体与血小板反应蛋白（P12）的结合与GMP-140蛋白（CD62）的表达相关（r = 0.76，p = 0.004）。体外血小板聚集缺陷与血小板活化标志物表达增加或血栓出血并发症之间无相关性。然而，在有出血或血栓并发症病史的5例患者中，有3例检测到循环活化血小板。这项初步研究的结果表明，部分而非全部骨髓增殖性疾病患者显示循环活化血小板数量增加。骨髓增殖性疾病中出血和血栓并发症与血小板上活化依赖性表位表达的关系需要进一步研究。
