中文摘要：

目的观察磁粒子和荧光染料双标人骨髓间充质干细胞归巢至大鼠急性损伤肝组织的示踪。方法以超顺磁性氧化铁（SPIO）和氯甲基苯甲酰氨（CM-Dil）标记永生化人骨髓间充质干细胞（UE7T-13）。普鲁士蓝染色检测细胞内铁,荧光显微镜和流式细胞仪检测CM-Dil标记阳性率。建立12只急性肝损伤大鼠模型,分为实验组（n=6）和对照组（n=6）,将标记细胞经尾静脉移植入实验组大鼠,未标记细胞移植入对照组大鼠。分别于移植前3h、移植后3h、3天、5天、7天应用MR T2^＊W、T2^＊map对大鼠活体成像,获得肝脏R2^＊值。并与肝脏组织切片普鲁士蓝染色和CM-Dil荧光表达情况对照。结果双标细胞的SPIO-PLL标记率接近100%,流式细胞仪检测CM-Dil标记阳性率达99.97%。实验组细胞移植后3天、5天肝脏R2＊值均较移植前明显升高（t=7.282、7.608,P均〈0.01）,对照组细胞移植后各时间点与移植前比较,R2^＊值差异均无统计学意义（F=0.99,P〉0.05）。普鲁士蓝阳性细胞主要分布于肝小叶中央静脉周围病变区,荧光显微镜下观察红色荧光阳性细胞与普鲁士蓝阳性细胞分布基本一致。结论 SPIO和CM-Dil可有效标记人永生化骨髓间充质干细胞（UE7T-13）,不影响细胞增殖能力,临床应用型1.5T MR可对磁粒子标记的UE7T-13进行肝归巢活体示踪,CM-Dil有助于证实存活干细胞的肝内定植。

英文摘要：

Objective To track the magneto-optical labeled human mesenchymal stem cells as they home into the acute liver failure of rats.Methods UE7T-13 were dual labeled with SPIO and CM-Dil.Prussian blue stain was performed to show intracellular irons,fluorescence microscope and flow cytometry detected for CM-Dil labeling rate.Acute liver damage models were established in 12 recipient rats including 6 in each of experimental group and control group.Cells was performed by tail vein injection with magneto-optical labeled UE7T-13（experimental group）or unlabeled UE7T-13（control group）.Serial MRI were performed before 3 hours and 3 hours,3,5,7 days after transplantation.R2^＊ value of liver was obtained.MR imaging findings were compared histologically with Prussian blue stain and CM-Dil.Results The labeling rate of SPIO-PLL approached 100% and the positive rate of CM-Dil was 99.97%.R2＊value in experimental group 3 and 5 days after transplantation were separately higher than that before transplantation（t=7.282,7.608,both P〈0.01）.No statistical differences was found between R2＊value before and after transplantation in control group（F=0.99,P〈0.105）.Red fluorescence and prussian blue-positive illustrated that positive-cells were mainly distributed in areas around centrolobular vein.Conclusion SPIO and CM-Dil can be used to dual-label UE7T-13 effectively without changing cells proliferation ability.Directional homing of labeled cells to the acute liver failure of rats after intravascular transplantation could be tracked in vivo with 1.5T MRI.CM-Dil is helpful to prove the living cell colonization in liver.