骨髓单个核细胞治疗颈动脉粥样硬化疗效的超声评价及机制分析

The preliminary studies found that bone marrow mononuclear cells (BMMNCs) exert repair function for injuried, but there are still some controversies about the influence of BMMNCs on carotid atherosclerosis. To further explore the influence of BMMNCs on the formation of carotid atherosclerosis, BMMNCs will be isolated from the bone marrow cavity of New Zealand white rabbits. Firstly, the characteristics of BMMNCs and their different cell components will be studied in vivo. In addition, BMMNCs and their different cell components were labeled with BrdU before transplantion. And then, BMMNCs and the different cellular components of BMMNCs will be transplanted into the body of New Zealand white rabbits to evaluate the therapeutic value of BMMNCs on carotid atherosclerosis with ultrasonic technique. In addition, the influence of CXCR4+CD45+ and CXCR4+CD45- components on the Pathological and physiological process of carotid atherosclerosis will also be studied by cmoparing with BMMNCs. This study was designed to vertify the influence of BMMNCs origined vascular endothelial cells and smooth muscle cells and dendritic cells on the formation of carotid atherosclerosis. It is great significant for the discovery of new therapeutic methods and potential therapeutic targets for cerebral infarction.

前期研究发现骨髓单个核细胞（Bone marrow mononuclear cells，BMMNCs）对损伤血管具有修复功能，但关于BMMNCs对颈动脉粥样硬化的治疗价值争议颇大；为评价BMMNCs对颈动脉粥样硬化斑块形成的影响，本项目拟首先从新西兰大白兔骨髓腔内分离BMMNCs，体外研究BMMNCs及其不同细胞成分的特点，并行BrdU标记。然后将BMMNCs及其不同细胞成分移植到新西兰大白兔颈动脉粥样硬化模型体内，利用超声评价BMMNCs及其不同细胞成分对颈动脉粥样硬化的治疗价值；并通过与BMMNCs比较，研究CXCR4+CD45+与CXCR4+CD45-细胞成分的定向分化能力及其对颈动脉粥样硬化病理生理过程的影响。拟探讨BMMNCs源性血管内皮细胞、平滑肌细胞及树突状细胞对经动脉粥样硬化斑块形成的影响，该研究对于发现颈动脉粥样硬化新的治疗手段及潜在治疗靶点。

本研究采用球囊损伤后连续8周高脂饮食的方法建立新西兰大白兔颈动脉粥样硬化模型，然后利用梯度离心法从这批大白兔骨髓腔内分离出骨髓单个核细胞，并采用BrdU进行标记；将标记完成的1×107个自体骨髓单个核细胞经耳缘静脉移分别植到相应大白兔动体内；利用免疫荧光技术评价BrdU标记的骨髓单个核细胞细胞向颈动脉硬化斑块的迁移情况，并从宏观及微观层面观察自体骨髓单个核细胞移植对颈动脉粥样硬化斑块发展的影响，我们发现：1.骨髓单个核细胞在移植后1天即可迁移至颈动脉粥样硬化斑块内，并存活14天以上；2.骨髓单个核细胞移植可显著减少斑块脂质含量及斑块体积；3.自体骨髓单个核细胞抑制颈动脉粥样硬化斑块内的氧化应激反应；4. 自体骨髓单个核细胞移植减少了炎症因子的分泌、促进了抗炎因子的表达；5.自体骨髓单个核细胞可分化内皮细胞，促进损伤内皮修复。上述研究结果证实自体骨髓单个核细胞移植可通过抑制斑块内的氧化应激、炎症反应及分化等机制抑制新西兰大白兔颈动脉粥样硬化的发展，为动脉粥样硬化的防治提供了新思路。另外，我们发现骨髓单个核细胞中主要抑制斑块进展的成分为CXCR4+CD45-部分，其促进了IL-10的分泌及降低了IL-6的分泌，具体机制尚需进一步研究中。