一种具有超大颗粒的遗传性巨血小板减少症初步报告

目的研究具有异常超微结构的遗传性巨血小板减少症的血小板形态与功能。方法采集患者外周静脉血，分离富血小板血浆，用流式细胞术结合多种抗血小板膜糖蛋白（GP）单克隆抗体测定血小板膜GPⅠb、GPⅡb、GPⅢa、p-选择素和CD63的表达；分别以常规超薄切片术和免疫电镜技术检测患者血小板及其异常超微结构的性质；用荧光分光光度法测定血小板5-羟色胺含量。结果患者及其父亲血小板表面GPⅠb、GPⅡb和GPⅢa的表达正常，阳性细胞百分数及平均荧光强度与正常对照基本相同，但P-选择素和CD63的表达较高；两者血小板内均有数量不等的高电子密度大颗粒，有膜包裹，且有胞吐现象。该颗粒P-选择素、CD63反应均阴性，不是异常的α颗粒或溶酶体；患者及其父亲血小板5-羟色胺含量正常。结论报道一种具有异常超微结构的遗传性血小板减少症，血小板内异常的高电子密度非特异性超大颗粒可能代表了一种新的遗传性血小板病。

A preliminary study of an inherited macrothrombocytopenic disorder with abnormal large granules

OBJECTIVE: To study the platelet morphology and function of an inherited macrothrombocytopenia disorder with abnormal large granules. METHODS: Platelet size and structure were investigated by both light microscopy and electron microscopy. The platelet membrane expression of GP I b, GP II b, GPIII a, P-selectin and CD63 were analyzed by using respective monoclonal antibodies. Platelet 5-hydroxy-tryptamine was measured with spectrophotofluorometer. RESULTS: Both the patient and her father had large granules in their platelets, with exocytosis being easily observed. The expressions of GP I b, GP II b and GP II a on the platelets were in normal range, while P-selectin and CD63 were somewhat increased. The abnormal large granules were not the alpha granules, lysosomes or dense bodies. CONCLUSION: Both morphological and functional abnormalities of the platelets from the patient are clearly distinguishable from other hereditary giant platelet disorders. It would probably represent a novel platelet disorder.