慢性特发性血小板减少性紫癜患者血小板凋亡的研究  

Investigation on platelet apoptosis in patients with chronic idiopathic thrombocytopenic purpura

作　　者：尹俊[1] 王建[2] 陈小勤[3] 余文俊[1] 廖敬源[1] 王端旭[2] 

机构地区：[1]汕头大学医学院第二附属医院血液科,广东汕头515041 [2]汕头大学医学院第二附属医院检验科,广东汕头515041 [3]汕头大学医学院临床技能培训中心,广东汕头515041

出　　处：《诊断学理论与实践》2010年第3期236-241,共6页Journal of Diagnostics Concepts & Practice

基　　金：广东省自然科学基金资助项目(9151802904000008)

摘　　要：目的:研究慢性特发性血小板减少性紫癜(ITP)患者血小板凋亡的情况。方法:临床确诊的慢性ITP患者40例,体检健康志愿者(健康对照)40名,分离血小板,采用流式细胞仪检测血小板线粒体跨膜电位(ΔΨm)和血小板表面磷脂酰丝氨酸(PS)的表达,采用蛋白印迹(Western blot)法检测caspase-3的激活和促凋亡蛋白Bak、Bax以及抗凋亡蛋白Bcl-xL的表达。结果:慢性ITP患者去极化血小板的数量明显多于健康对照者,血小板线粒体跨膜电位显著低于健康对照者(P<0.01)。从血小板提取的蛋白质经Western blot检测表明,慢性ITP患者血小板中的caspase-3裂解出一条17ku大小的条带,提示caspase-3被激活,而且凝溶胶蛋白在活化的caspase-3作用下裂解出一条47ku大小的条带。慢性ITP患者的血小板中,促凋亡蛋白Bak和Bax的表达均强于健康对照者,而抗凋亡蛋白Bcl-xL的表达则弱于健康对照者。此外,慢性ITP患者表达PS的血小板数量显著高于健康对照者(P<0.01)。结论:慢性ITP患者的血小板存在着线粒体途径的凋亡现象,血小板凋亡可能是慢性ITP的发病机制之一。Objective Platelet apoptosis in patients with chronic idiopathic thrombocytopenic purpura （ITP） was investigated.Methods Platelets were isolated from 40 patients with chronic ITP and 40 healthy volunteers.Platelet mitochondrial inner transmembrane potential （ΔΨm） and expression of phosphatidylserine （PS） on surface of platelet were examined by using flow cytometry.Activation of caspase-3 and expressions of pro-apoptotic proteins such as Bak,Bax and anti-apoptotic protein such as Bcl-xL were determined by Western blot.Results Amount of depolarized platelets was more and ΔΨm was lower in patients with chronic ITP than that in healthy volunteers （P0.01）.Western blot analysis showed that in platelets of patients with chronic ITP,caspase-3 was cleaved with the releasing of a segment of 17 ku,which indicated that caspase-3 was activated.Moreover,gelsolin was cleaved by activated caspase-3 and a segment of 47 ku was released.Expressions of pro-apoptotic proteins such as Bak and Bax were increased and expression of antiapoptotic protein such as Bcl-xL was decreased in platelets of patients with chronic ITP.Flow cytometry showed that the quantity of platelets expressing PS was more in patients with chronic ITP than that in healthy volunteers （P0.01）.Conclusions Platelet apoptosis via mitochondrial pathway is observed in patients with chronic ITP,which may be one of the pathogenic mechanisms of chronic ITP.

关 键 词：慢性特发性血小板减少性紫癜 血小板 细胞凋亡 

分 类 号：R588.2[医药卫生—内分泌]