Chen Xiang-Qi, Chen Liang-Long, Fan Lin, Fang Jun, Chen Zhao-Yang, Li Wei-Wei
Fujian Institute of Coronary Artery Disease and Department of Cardiology, Union Hospital, Fujian Medical University, Fuzhou, Fujian 350001, China.
Fujian Institute of Coronary Artery Disease and Department of Cardiology, Union Hospital, Fujian Medical University, Fuzhou, Fujian 350001, China.
Biochem Biophys Res Commun. 2014 Apr 25;447(1):145-51. doi: 10.1016/j.bbrc.2014.03.131. Epub 2014 Apr 6.
The aim of this study was to investigate whether the modification of bone marrow-derived mesenchymal stem cells (BMSCs) with the fused FGF4 (fibroblast growth factor 4)-bFGF (basic fibroblast growth factor) gene could improve the expression and secretion of BFGF, and increase the efficacies in repairing infarcted myocardium. We used In-Fusion technique to construct recombinant lentiviral vectors containing the individual gene of bFGF, enhanced green fluorescent protein (EGFP), or genes of FGF4-bFGF and EGFP, and then transfected these lentiviruses into rat BMSCs. We conducted an in vitro experiment to compare the secretion of bFGF in BMSCs infected by these lentiviruses and also examined their therapeutic effects in the treatment of myocardial infraction in a rodent study. Sixty rats were tested in the following five conditions: Group-SHAM received only sham operation as controls; Group-AMI received only injection of placebo PBS buffer; Group-BMSC, Group-bFGF and Group-FGF4-bFGF received implantation of BMSCs with empty lentivirus, bFGF lentivirus, and FGF4-bFGF lentivirus, respectively. Our results found out that the transplanted FGF4-bFGF BMSCs had the highest survival rate, and also the highest myocardial expression of bFGF and microvascular density as evidenced by Western blotting and immunohistochemistry, respectively. As compared to other groups, the Group-FGF4-BFGF rats had the lowest myocardial fibrotic fraction, and the highest left ventricular ejection fraction. These results suggest that the modification of BMSCs with the FGF4-bFGF fused gene can not only increase the expression of bFGF but also improve its secretion. The FGF4-bFGF BMSCs thus can enhance the survival of the transplanted cells, diminish myocardial fibrosis, promote myocardial angiogenesis, and improve cardiac functions.
本研究的目的是探讨用融合的FGF4（成纤维细胞生长因子4）-bFGF（碱性成纤维细胞生长因子）基因修饰骨髓间充质干细胞（BMSCs）是否能提高BFGF的表达和分泌，并增强修复梗死心肌的效果。我们使用In-Fusion技术构建了包含bFGF单个基因、增强型绿色荧光蛋白（EGFP）或FGF4-bFGF和EGFP基因的重组慢病毒载体，然后将这些慢病毒转染到大鼠BMSCs中。我们进行了一项体外实验，比较这些慢病毒感染的BMSCs中bFGF的分泌情况，并在一项啮齿动物研究中检查了它们在治疗心肌梗死中的治疗效果。60只大鼠在以下五种条件下进行测试：假手术组仅接受假手术作为对照；急性心肌梗死组仅注射安慰剂PBS缓冲液；BMSC组、bFGF组和FGF4-bFGF组分别接受用空慢病毒、bFGF慢病毒和FGF4-bFGF慢病毒转染的BMSCs植入。我们的结果发现，移植的FGF4-bFGF BMSCs具有最高的存活率，并且通过蛋白质印迹法和免疫组织化学分别证明其bFGF的心肌表达和微血管密度最高。与其他组相比，FGF4-BFGF组大鼠的心肌纤维化分数最低，左心室射血分数最高。这些结果表明，用FGF4-bFGF融合基因修饰BMSCs不仅可以增加bFGF的表达，还可以改善其分泌。因此，FGF4-bFGF BMSCs可以提高移植细胞的存活率，减少心肌纤维化，促进心肌血管生成，并改善心脏功能。
