THERAPEUTIC ANGIOGENESIS INDUCED BY AUTOLOGOUS BONE MARROW CELLS IMPLANTATION FOR THE TREATMENT OF ISCHEMIC DISEASES

骨髓单个核细胞(BM-MNCs)移植可以诱导治疗性血管生成，但BM-MNCs的最佳细胞比例和诱导治疗性血管生成的最佳输送途径尚不清楚。用干细胞受体(CD117)抗体从小鼠成熟的BM-MNCs中分离干细胞。培养14天后，CD117~+细胞分泌的血管内皮生长因子水平是CD117~-细胞(P&lt；0.001)的10倍以上。CD117~-细胞大部分死亡，但CD117~+细胞在培养14d内生长良好，分化为内皮细胞。将CD117+细胞(2×10^5)、CD117-细胞(9.8×10^6)和总BM-MNCs(1×10^7)植入小鼠缺血后肢。治疗14天后，移植CD117~+细胞的小鼠的后肢缺血血流灌注量显著高于移植CD117~-细胞的小鼠(P&lt；0.01)，但与移植BM-MNCs的小鼠相比无显著差异。这些结果表明CD117+干细胞在骨髓细胞移植诱导的治疗性血管生成中起关键作用。然后，我们在大鼠急性心肌梗死模型上观察了不同输送途径的BM-MNCs诱导治疗性血管生成的有效性。结扎左冠状动脉升支后，BM-MNC(1×10~(-7))肌内注射(IM组)或静脉注射(IV组)。IM组的BM-MNCs存活率明显高于IV组。IM组梗死区血流量和心脏射血分数均显著高于IV组。这些结果表明，局部肌肉注射BM-MNCs诱导的血管生成能力优于静脉注射。

Therapeutic angiogenesis can be induced by the implantation of bone marrow mononuclear cells (BM-MNCs), but the best cell fraction in BM-MNCs and the best delivery road for inducing therapeutic angiogenesis kept unclear.At first, we investigated the roles of stem cell fractions in BM-MNCs in this treatment. Stem cells were separated from mature BM-MNCs of mice using the antibody to stem cell receptor (CD117). More than ten-fold higher levels of VEGF were secreted from the CD117^+ cells than from the CD117^- cells (P< 0.001) 14 days after culture. Most of the CD117^- cells died, but the CD117^+ cells grew well and differentiated into endothelial ceils within 14 days of culture. CD117^+ cells (2 x 10^5), CD117^- cells (9.8 x 10^6), and total BM-MNCs (1 x 10^7) were also implanted into the ischemic hindlimbs of mice. The blood perfusion of the ischemic hindlimbs was significantly higher in the CD117^+ cell-implanted mice than in the CD117^- cell-implanted mice (P<0.01), but did not differ significantly from the BM-MNCs cell-implanted mice, 14 days after treatment. These results indicated that CD117^+ stem cells play a key role in the therapeutic angiogenesis induced by bone marrow cell implantation.Then, we investigated the potency of therapeutic angiogenesis inducing by BM-MNCs using different delivery roads in an acute myocardium infarction model in rats. After the ligation of left ascending coronary artery, BM-MNCs (1 x 10^7) were given intramuscularly (IM group) or intravenously (IV group). The survival of BM-MNCs was better in the IM group than the IV group. Furthermore, both the blood flow of infarction area and the cardiac ejection fraction were significantly higher in the IM group than the IV group. These results indicated that the angiogenic potency inducing by BM-MNCs implantation was better by local intramuscularly injection than by intravenous delivery.