Department of Cardiology, the Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
Can J Cardiol. 2011 Nov-Dec;27(6):818-25. doi: 10.1016/j.cjca.2011.07.633. Epub 2011 Oct 20.
Our objective was to trace and evaluate intracoronary transplanted mesenchymal stem cells (MSCs) labelled with superparamagnetic iron oxide (SPIO) by using magnetic resonance imaging (MRI) in a swine model of myocardial infarction (MI).
MSCs were transfected with a lentiviral vector carrying the gene encoding green fluorescent protein (GFP) and labelled in vitro with SPIO. At 2 weeks after MI, swine were randomized to intracoronary transplantation of dual-labelled MSCs (n=10), MSC-GFP (n=10), and saline (n=5). MRI examination was performed with a 1.5-T clinical scanner at 24 hours, 3 weeks, and 8 weeks after cell transplantation. Signal intensity changes, cardiac function, and MI size were measured by means of MRI. The correlation between MRI findings and histomorphologic findings was also investigated.
MSCs could be efficiently and safely labelled with SPIO and GFP, and multipotentiality was not affected, especially for cardiomyocyte-like cell differentiation. Signal intensity on T2*-weighted imaging decreased substantially in the interventricular septum 24 hours after injection of MSCs. The intensity of hypointense signals appeared to increase throughout the later time points. Both dual-labelled MSCs and MSC-GFP could dramatically reduce the size of MI and improve cardiac function. Histologic data revealed that cells positive for Prussian blue stain were found mainly in the border zone, which also showed green fluorescence.
In vivo 8-week tracing of dual-labelled MSCs can be achieved by MRI. Intracoronary transplantation of dual-labelled MSCs can increase cardiac function and reduce the size of MI in a swine model.
我们的目的是通过磁共振成像（MRI）在猪心肌梗死（MI）模型中追踪和评估超顺磁性氧化铁（SPIO）标记的骨髓间充质干细胞（MSCs）。
MSCs 被转染带有编码绿色荧光蛋白（GFP）基因的慢病毒载体，并在体外用 SPIO 标记。在 MI 后 2 周，猪被随机分为冠状动脉内移植双标记 MSCs（n=10）、MSC-GFP（n=10）和盐水（n=5）组。细胞移植后 24 小时、3 周和 8 周，使用 1.5-T 临床扫描仪进行 MRI 检查。通过 MRI 测量信号强度变化、心功能和 MI 大小。还研究了 MRI 结果与组织形态学结果之间的相关性。
MSCs 可以有效地、安全地用 SPIO 和 GFP 标记，并且多能性不受影响，特别是对于心肌样细胞分化。注射 MSCs 后 24 小时，室间隔 T2*-加权成像上的信号强度显著降低。低信号强度的强度似乎在随后的时间点增加。双标记 MSCs 和 MSC-GFP 均能显著减小 MI 大小并改善心功能。组织学数据显示，普鲁士蓝染色阳性的细胞主要位于边缘区，也显示绿色荧光。
通过 MRI 可以实现双标记 MSCs 的体内 8 周追踪。冠状动脉内移植双标记 MSCs 可以增加心功能，减少猪模型中的 MI 大小。
