Liu Zai-Yi, Wang Ying, Wang Guang-Yi, Li Xiao-Hong, Li Yan, Liang Chang-Hong
Department of Radiology, Guangdong General Hospital, Guangzhou 510080, China.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao. 2009 Apr;31(2):187-91.
To investigate the feasibility of in vivo magnetic resonance imaging (MRI) tracking of transplanted adipose-derived stem cells (ADSCs) labeled with superparamagnetic iron oxide (SPIO) in rat heart.
ADSCs were labeled with poly-L-lysine (PLL)-SPIO complexes. Intracellular iron uptake was identified by Prussian blue stain and transmission electromicroscopy. Trypan blue staining was used to test the viability of the labeled cells. In vitro MRI of labeled cells was performed. SPIO-labeled ADSCs were transplanted into normal rat hearts and were in vivo imaged with MRI. Image findings on MRI were correlated with histological findings of the rat hearts.
The labeling efficacy of ADSCs with PLL-SPIO was nearly 100%. Light microscopy revealed the SPIO particles were located in the cytoplasm of the ADSCs by Prussian blue staining. Transmission electromicroscopy revealed that the SPIO particles were located in the endosomes in the cytoplasm. There was no significantly deference in viability between labeled and unlabeled groups demonstrated by Trypan blue test (P > 0.05). MRI showed signal loss in gel mixed with labeled cells as compared with the unlabeled cells group and blank group. Signal void on rat hearts were demonstrated on MRI and were well correlated with histological findings where Prussian-blue-stain positive cells presented.
MRI can be used to in vivo track the transplanted ADSCs labeled with SPIO into rat hearts and facilitate to understand the conditions of the labeled cells in the transplanted areas.
探讨超顺磁性氧化铁（SPIO）标记的脂肪来源干细胞（ADSCs）在大鼠心脏内进行磁共振成像（MRI）活体追踪的可行性。
用聚-L-赖氨酸（PLL）-SPIO复合物标记ADSCs。通过普鲁士蓝染色和透射电子显微镜鉴定细胞内铁摄取情况。用台盼蓝染色检测标记细胞的活力。对标记细胞进行体外MRI检查。将SPIO标记的ADSCs移植到正常大鼠心脏，并通过MRI进行活体成像。MRI图像表现与大鼠心脏的组织学表现相关。
PLL-SPIO对ADSCs的标记效率近100%。光学显微镜下普鲁士蓝染色显示SPIO颗粒位于ADSCs的细胞质中。透射电子显微镜显示SPIO颗粒位于细胞质中的内体中。台盼蓝试验显示标记组和未标记组的活力无显著差异（P>0.05）。与未标记细胞组和空白组相比，MRI显示与标记细胞混合的凝胶中有信号丢失。MRI显示大鼠心脏出现信号缺失，且与普鲁士蓝染色阳性细胞所在的组织学表现密切相关。
MRI可用于在体追踪SPIO标记的ADSCs移植到大鼠心脏内的情况，并有助于了解移植区域标记细胞的状况。
