高频超声评价自体骨髓间充质干细胞移植对免缺血肢体血管再生的影响

背景:研究发现干细胞可分化为血管内皮细胞,并可进一步分化形成新生毛细血管,自体骨髓间充质干细胞移植促进血管再生正是利用这一原理达到治疗下肢缺血的目的.目的:采用高频二维超声及彩色多普勒血流成像检测评价自体骨髓间充质干细胞移植后兔缺血肢体血管再生的情况.设计、时间及地点:随机对照动物实验,于2007-03/2008-04在无锡市第三人民医院完成.材料:新西兰大白兔24只,随机分为模型对照组、细胞移植组,12只/组.方法:2组兔均建立后肢缺血动物模型,造模1周后,细胞移植组取体外分离培养的Brdu标记的自体骨髓间充质干细胞,在腓肠肌部位皮下分多点注射,细胞悬液总体积0.5 mL,细胞总量2×105个;模型对照组于相同部位注射等量生理盐水.主要观察指标:对兔股动脉及股浅动脉起始段行高频二维超声及彩色多普勒血流成像检测,测量股动脉血管内径、血流峰值速度、血流加速时间;取缺血部位肌肉组织,免疫组织化学染色检测移植细胞分布情况及病理学检查血管再生情况.结果:移植后2周,高频超声检查细胞移植组兔股动脉内径、血流峰值速度均大于模型对照组,血流加速时间小于模型对照组(P<0.01).免疫组织化学染色后移植部位可见抗Brdu染色阳性细胞的存在,病理切片示细胞移植组血管密度明显高于模型对照组.结论:自体骨髓间充质干细胞移植具有促进血管生成的作用,有望成为一种简单有效的治疗下肢缺血的方法,同时高频超声检测股动脉为自体骨髓间充质干细胞移植效果评价提供了有效实用的方法.

Effects of autologous bone marrow mesenchymal stem cell transplantation on angiogenesis in rabbit ischemic limbs A high-frequency ultrasound evaluation

BACKGROUND:Several studies have demonstrated that stem cells can differentiate into vascular endothelial cells, and then further differentiate and form blood capillary. Based on this principle, autologous bone marrow mesenchyrnal stem cell (BMSC) transplantation promotes angiogenesis to treat ischemia in lower limb.OBJECTIVE: To evaluate the angiogenesis in rabbit ischemic limbs following autologous BMSC transplantation using high-frequency two-dimensional ultrasound detection in conjunction with Doppler color-flow imaging examination. DESIGN, TIME AND SEI-FING: A randomized, controlled, animal experiment was performed in the Third People's Hospital of Wuxi between March 2007 and April 2008.MATERIALS: Twenty-four New Zealand rabbits were randomized to a control group and a cell transplantation group, with 12 rabbits in each.METHODS: Ischemia in lower limbs was induced in all rabbits. One week following ischemia induction, the cell transplantation group was injected with 0.5 mL cell suspension, comprising 2×106 BrdU-labeled autologous BMSCs cultured in vitro, through multiple sites in the region of gastrocnemius muscle. Simultaneously, the control group received the same amount of physical saline in the same region.MAIN OUTCOME MEASURES: The initial segment of rabbit femoral artery and superficial femoral artery was subjected to high-frequency two-dimensional ultrasound and Doppler color-flow imaging examinations to measure femoral artery vascular internal diameter, blood flow peak velocity, and blood flow acceleration time. Ischemic muscular tissue was taken for immunohistochemical staining to detect transplanted cell distribution and for pathological examination of angiogenesis. RESULTS: Two weeks following autologous BMSC transplantation, high-frequency ultrasound results revealed that femoral artery internal diameter and blood flow peak velocity were greater, but blood flow acceleration time was shorter, in the cell transplantation group than in the control group (P<0.01). Immunohistochemical staining results demonstrated the presence of BrdU-positive cells. Pathological sections displayed that vascular density was significantly higher in the cell transplantation group than ih the control group. CONCLUSION: Autologous BMSC transplantation is a promising, simple, and effective method of treating ischemia in lower limbs owing to its promotion of angiogenesis. Meanwhile, high-frequency ultrasound detection of femoral artery is an effective, practical method to evaluate the clinical outcomes of autologous BMSC transplantation.