摘要
目的应用超声分子成像动态评估动脉粥样硬化(AS)小鼠模型中血小板与血管内皮相互作用在AS病变炎性进展中的作用。方法60只载脂蛋白E基因敲除(ApoE-/-)小鼠高脂饮食喂养建立AS模型作为实验组;40只C57BL/6J小鼠普通饮食喂养作为对照组。生物素-亲和素桥接法构建携重组vWF-A1血小板靶向微泡(Mb-A1),携VCAM-1单克隆抗体的靶向微泡(Mb-VCAM1)以及携IgG单克隆抗体微泡(Mb-ctrl),体外与活体动物实验评估Mb-A1识别血管内皮表面血小板的能力;超声分子成像观测不同周龄实验组与对照组小鼠升主动脉内来自Mb-A1、Mb-VCAM1、Mb-ctrl的信号强度的变化,免疫荧光染色观察分析AS小鼠升主动脉血管内皮表面血小板和单核/巨噬细胞的表达与分布。结果①体外实验中,荧光显微镜下可见大量Mb-A1黏附于活化血小板表面;②阻滞32周龄AS小鼠95%血小板后,升主动脉内来自Mb-A1的信号强度显著降低(P<0.05);③各周龄AS小鼠中,升主动脉内来自Mb-A1与Mb-VCAM1的信号强度高于同周龄对照组小鼠,且随着周龄增长进行性增长,差异有统计学意义(P<0.05);④升主动脉内皮表面活化血小板自8周龄起随周龄增长进行性增加,且与单核/巨噬细胞的分布呈部分重叠。结论血小板作为一种炎性因子,通过与血管内皮的相互作用参与AS炎性病变进行性发展的过程。
Objective To assess the role of activated platelets in the inflammatory procession of atherosclerosis(AS)by ultrasound molecular imaging.Methods Sixty ApoE-/-mice were fed with high fat diet to establish AS model as experimental group,and 40 C57BL/6J mice were fed with normal diet as control group.Biotin-avidin bridging method was used to construct platelet-targeted microbubbles with recombinant vWF-A1 domain(Mb-A1),microbubbles carrying monoclonal antibodies to VCAM-1(Mb-VCAM1)and microbubbles carrying IgG monoclonal antibody(Mb-ctrl).In vitro and in vivo experiments were carried out to evaluate the ability of Mb-A1 to target platelets on vascular endothelial surface.Contrast enhanced ultrasound molecular imaging of proximal ascending aorta was performed with Mb-A1,Mb-VCAM1 and Mb-ctrl.The expression and distribution of platelets and monocytes/macrophages on the endothelium of ascending aorta of AS mice were observed and analyzed by immunofluorescence staining.Results①A large number of Mb-A1 adhering to the surface of activated platelets coated in Petri dishes were observed under fluoresce.②After platelet immune-depletion in 30-week AS mice,the signal intensity of Mb-A1 decreased significantly in ascending aorta,while that of Mb-ctrl has no obvious change(P<0.05).③In ApoE-/-mice,signals from platelet targeted microbubbles increased from 8 to 32 weeks of age in ApoE-/-mice,which coincided with the increase of signals from VCAM-1 targeted microbubbles(P<0.05).④Activated platelets on the endothelial surface of ascending aorta increased progressively with age from 8 weeks,and partly overlapped with the distribution of monocytes/macrophages.Conclusions Platelets contribute to the initiation and progression of atherosclerosis as an inflammatory mediator through the interaction with vascular endothelium.
作者
孙睿颖
刘娅妮
田洁
赵巍
张隽
翁雅慧
刘红云
Sun Ruiying;Liu Yani;Tian Jie;Zhao Wei;Zhang Jun;Weng Yahui;Liu Hongyun(Department of Medical Ultrasound,Tongji Hospital,Huangzhong University of Science and Technology,Wuhan 430030,China)
出处
《中华超声影像学杂志》
CSCD
北大核心
2019年第12期1076-1081,共6页
Chinese Journal of Ultrasonography
基金
国家自然科学基金资助项目(81371581)。
关键词
超声分子成像
靶向微泡
动脉粥样硬化
炎症
血小板
Contrast enhanced ultrasound
Targeted microbubble
Atherosclerosis
Inflammation
Platelet
