骨骼肌成肌细胞与血管生成祖细胞联合移植后的新生血管生成可提高缺血性心力衰竭中的细胞植入率并降低凋亡率。

Neoangiogenesis after combined transplantation of skeletal myoblasts and angiopoietic progenitors leads to increased cell engraftment and lower apoptosis rates in ischemic heart failure.

作者信息

Bonaros Nikolaos, Rauf Rauend, Werner Ernst, Schlechta Bernhard, Rohde Eva, Kocher Alfred, Bonatti Johannes, Laufer Guenther

机构信息

Department of Cardiac Surgery, Innsbruck Medical University, Anichstrasse 35, A-6020, Innsbruck, Austria.

出版信息

Interact Cardiovasc Thorac Surg. 2008 Apr;7(2):249-55. doi: 10.1510/icvts.2007.162917. Epub 2007 Oct 9.

DOI:10.1510/icvts.2007.162917

PMID:17925321

Abstract

OBJECTIVES

We previously reported that combined transplantation of skeletal myoblasts and AC-133+ cells leads to improved left ventricular function, reduced infarct size and myocardial apoptosis in a model of chronic ischemia. The aim of this study is to elucidate on the possible mechanisms and to assess new implications in increasing cell therapy efficacy in chronic ischemia.

METHODS

Heart failure was induced by LAD-ligation in nude rats. (a) Homologous skeletal myoblasts (SM), (b) human derived AC-133+ cells (SC), (c) combination of both cells (Comb) and (d) culture medium (CM) were injected in the infarct and peri-infarct area, respectively, four weeks after infarction. Cell engraftment was detected by fluorescence microscopy and confirmed by immunohistochemical techniques. Cardiac gene expression levels of VEFG-A, cardiac troponin, ACTA2, SDF-1, TGF-beta-1, were assessed by RT-PCR.

RESULTS

Both cell types were detected in the injection areas four weeks after cell transplantation. Double cell therapy led to increased cell engraftment (SM: 52+/-13/mm(2), SC: 45+/-8 in the combination group vs. SM: 31+/-9 and 23+/-7 in the monotherapy groups, P=0.007). This effect was confirmed using PCR. Apoptotic index among engrafted cells was significantly lower in the Comb group (Comb: 0.53+/-0.12 for myoblasts and 0.34+/-0.09 for SC, vs. SM: 0.76+/-0.19 and SC: 0.63+/-0.16, P=0.013). Expression of cardiac troponin was higher in the combination group in the peri-infarct area. Evaluation of capillary density revealed increased angiogenesis in the combination group (Comb: 12.3+/-2.3, SM: 5.2+/-1.2, SC: 8.3+/-1.8, P=0.002). Neoangiogenesis was associated with higher levels of VEGF-A and TGF-beta in the injection areas as detected by RT-PCR. The higher SDF-1 expression in the injected areas implies an increased secretion of chemoattractants by the injected cells, which suggests that the effect of combined cell transplantation is mainly associated with paracrine mechanisms.

CONCLUSIONS

The mechanism of functional improvement after combined transplantation of skeletal myoblasts and AC-133+ progenitors in ischemic heart failure is mainly associated with increased angiogenesis based on paracrine factors, which leads to improved survival and lower apoptosis rates of the injected cells.

摘要

目的

我们之前报道过，在慢性缺血模型中，联合移植骨骼肌成肌细胞和AC-133+细胞可改善左心室功能、减小梗死面积并减少心肌细胞凋亡。本研究的目的是阐明可能的机制，并评估在提高慢性缺血细胞治疗疗效方面的新意义。

方法

通过结扎左冠状动脉前降支在裸鼠中诱导心力衰竭。在梗死后四周，分别将(a)同源骨骼肌成肌细胞(SM)、(b)人源AC-133+细胞(SC)、(c)两种细胞的组合(Comb)和(d)培养基(CM)注射到梗死区和梗死周边区。通过荧光显微镜检测细胞植入情况，并通过免疫组织化学技术进行确认。通过逆转录聚合酶链反应(RT-PCR)评估血管内皮生长因子A(VEFG-A)、心肌肌钙蛋白、平滑肌肌动蛋白(ACTA2)、基质细胞衍生因子-1(SDF-1)、转化生长因子-β1(TGF-β-1)的心脏基因表达水平。

结果

细胞移植四周后，在注射区域均检测到了两种细胞类型。联合细胞治疗导致细胞植入增加(联合组中SM为52±13/mm²，SC为45±8，而单治疗组中SM为31±9和23±7，P = 0.007)。使用PCR证实了这一效果。联合组中植入细胞的凋亡指数显著更低(联合组中，成肌细胞为0.53±0.12，SC为0.34±0.09，而SM组为0.76±0.19，SC组为0.63±0.16，P = 0.013)。梗死周边区联合组中心肌肌钙蛋白的表达更高。毛细血管密度评估显示联合组中血管生成增加(联合组为12.3±2.3，SM组为5.2±1.2，SC组为8.3±1.8，P = 0.002)。通过RT-PCR检测发现，注射区域的新生血管生成与更高水平的VEGF-A和TGF-β相关。注射区域中更高的SDF-1表达意味着注射细胞分泌的趋化因子增加，这表明联合细胞移植的效果主要与旁分泌机制相关。