经冠状静脉逆行灌注碱性成纤维细胞生长因子对骨髓间充质干细胞体内分化的影响

背景：体外研究显示，碱性成纤维细胞生长因子能促进骨髓间充质干细胞向心肌样细胞分化。然而，在体内环境下经冠状静脉逆行灌注碱性成纤维细胞生长因子能否促进骨髓间充质干细胞分化尚不明确。目的：探讨经冠状静脉逆行灌注碱性成纤维细胞生长因子对骨髓间充质干细胞在体内分化的影响。方法：①杂种犬12只，采用密度梯度离心与贴壁培养法在体外分离、培养骨髓间充质干细胞，增强型绿色荧光蛋白慢病毒载体转染骨髓间充质干细胞并分析转染率。②开胸结扎法建立急性心肌梗死模型，1周后将存活犬（n=10）随机分为骨髓间充质干细胞组（n=5）和碱性成纤维细胞生长因子＋骨髓间充质干细胞组（n=5），采用OTW球囊经冠状静脉逆行灌注碱性成纤维细胞生长因子和增强型绿色荧光蛋白标记的骨髓间充质干细胞。移植后1周，免疫荧光法比较两组梗死心肌内增强型绿色荧光蛋白阳性细胞共表达Ⅷ因子和肌钙蛋白I的数量。结果与结论：增强型绿色荧光蛋白慢病毒成功转染骨髓间充质干细胞，转染率达85%；灌注后免疫荧光显示，23.5%的切片可以看到增强型绿色荧光蛋白标记的骨髓间充质干细胞阳性细胞；碱性成纤维细胞生长因子＋骨髓间充质干细胞组增强型绿色荧光蛋白共表达Ⅷ因子和肌钙蛋白 I 的细胞数量明显高于骨髓间充质干细胞组（P＆lt;0.05）。因此，经冠状静脉逆行灌注碱性成纤维细胞生长因子能更有效地促进骨髓间充质干细胞分化成血管内皮细胞和心肌细胞；采用该途径联合灌注碱性成纤维细胞生长因子和骨髓间充质干细胞有望发挥协同作用，更好地促进心脏修复。

Effects of basic fibroblast growth factor via coronary venous retroperfusion on bone marrow mesenchymal stem cell differentiation in vivo

BACKGROUND：In vitro studies have demonstrated that basic fibroblast growth factor （bFGF） promote the differentiation of bone marrow mesenchymal stem cells （BMSCs） into cardiomyocyte-like cells. However, it is unclear whether coronary venous retroperfusion of bFGF stimulates BMSCs differentiation in vivo. OBJECTIVE：To evaluate the effects of coronary venous retroperfusion of bFGF on BMSCs differentiation in vivo. METHODS：BMSCs from 12 dogs were isolated by density gradient centrifugation and expanded in vitro. These cells were transfected by enhanced green fluorescence protein （EGFP） lentiviral vector and the transfection efficiency was analyzed. Acute myocardial infarction was induced by ligation of left anterior descending coronary artery. After 1 week, 10 survival animals were randomized to BMSCs group （n=5） and bFGF＋BMSCs group （n=5）.＆amp;nbsp;bFGF-and EGFP-positive BMSCs were reversely infused via coronary vein using over-the-wire bal oon catheter. One week after infusion, the number of EGFP-positive cells co-staining factor VIII and troponin I was compared between the two groups by immunofluorescence method. RESULTS AND CONCLUSION：BMSCs were successful y transfected by EGFP and the transfection efficiency was 85%. Immunofluorescence showed that EGFP-positive BMSCs were observed in 23.5%of slides. There were more EGFP-positive cells co-staining VIII and troponin I in the bFGF＋BMSCs group than in the BMSCs group （P＆lt;0.05）. Thus, the coronary venous retroperfusion of bFGF enhances the differentiation of BMSCs into vascular endothelial cells and cardiomyocytes. Combined delivery of bFGF and BMSCs can exert a synergistic effect to promote cardiac repair.