新型MRI磁标记技术对兔骨髓基质干细胞自体皮下移植进行活体示踪的研究  

Superparamagnetic iron oxide-labeled bone marrow stromal stem cells tracked in vivo by magnetic resonance imaging after autologous transplantation into subcutaneous tissue in rabbits

作　　者：金旭红[1] 杨柳[1] 段小军[1] 王晓宇[1] 王富友[1] 李忠[1] 谭洪波[1] 

机构地区：[1]第三军医大学附属西南医院关节外科中心,重庆400038

出　　处：《中华创伤骨科杂志》2008年第2期154-159,共6页Chinese Journal of Orthopaedic Trauma

基　　金：国家自然科学基金（30300079,30670527）;全军十一五医药卫生科研重点基金（06G079）

摘　　要：目的利用超顺磁性氧化铁（SPIO）粒子标记骨髓基质干细胞（BMSCs），探讨用0．2T MRI活体示踪自体皮下移植磁化标记BMSCs的分布和迁移的可行性。方法从兔骨髓中分离培养BMSCs，实验组经体外采用SPIO和BrdU双重标记后，与壳聚糖复合植入兔自体大腿皮下。设立自体皮下移植未标记BMSCs组和皮下单纯注射SPIO组为对照组，每组6只。于术后1、5d及2、4、8周连续行MRI梯度回波T2加权（GRE T2^＊WI）扫描序列对磁标记细胞成像示踪，并行组织学检查。结果磁标记细胞普鲁士蓝染色和电镜检查显示细胞胞浆内含致密铁颗粒。磁标记后自体皮下移植的兔BMSCs在GRE T2^＊WI序列成像时产生特征性的低信号改变至少维持8周，并观察到从移植部位发出低信号线进入宿主组织。组织学检查显示宿主组织中发现普鲁士蓝阳性细胞和Brdu阳性细胞。结论体外SPIO能有效地标记BMSCs，利用0．2T MRI活体示踪体自体皮下移植的磁标记兔BMSCs分布和迁移是可行的。Objective To study the feasibility of magnetic resonance imaging tracking of auto-transplanted nanometer superparamagnetic iron oxide（SPIO） - labeled bone marrow stromal stem cells （BMSCs） in vivo in the subcutaneous tissue in rabbits. Methods Rabbit BMSCs were isolated, purified, expanded, and in vitro co-incubated with SPIO （25 μg/mL） complexed to protamine sulfate （Pro） transfection agents for 12 h. Subsequently BMSCs were grown in medium containing 5-bromo-2-deoxyuridiBe （BrdU） for 2 h. After co-labeled, BMSCs were encapsulated in chitosan and glycerophosphate （C-GP） gel. Autologous co-labeled BMSCs encapsulated in C-GP gel constructs were injected into the thigh subcutaneous tissue of rabbits. All rabbits were subjected to a clinical 0. 2 T MRI using a T2^＊-weighted gradient-echo （GRE T2^＊WI） sequence at 1 day, 5 days, 2 weeks, 4 weeks, and 8 weeks after implantation. Animals were divided into 3 groups： 1 ） injected with SPIO and BrdU co-labeled BMSCs seeded in chitosan and glycerophosphate （C-GP） gel （experimental, n = 6）; 2） injected with BrdU labeled BMSCs seeded in chitosan and glycerophosphate （C-GP） gel （control, n =6）; 3） injected with SPIO alone （control, n = 2）. Results Intracytoplasmic nanoparticles stained with Prussian blue were observed clearly by transmission electron microscopy in the SPIO-labeled cells. At injection sites low signal intensity could be observed on MRI examination with the scanning sequences of GRE T2^＊WI. Low signal intensity lines could be observed targeting to the host tissue areas in the experimental group. Conclusions SPIO can be used to label BMSCs in vitro efficiently. 0. 2T MRI in vivo tracking of the auto-transplanted SPIO-labeled BMSCs in the subcutaneous tissue is effective.

关 键 词：骨髓细胞 移植 磁共振成像 超顺磁性氧化铁 

分 类 号：R445.2[医药卫生—影像医学与核医学]