超顺磁性氧化铁纳米粒子标记滑膜间充质干细胞的实验研究

Superparamagnetic iron oxide labels synovial mesenchymal stem cells

目的探讨超顺磁性氧化铁纳米颗粒（SPIO）标记滑膜间充质干细胞（SMSC）的可行性及标记前后细胞生物学特性的变化。方法将体外分离培养、纯化及鉴定后的兔膝关节SMSC加入不同浓度的SPIO标记液在37℃二氧化碳培养箱孵育,24 h后普鲁士蓝染色和透射电镜下观察标记情况,并比较标记前后SMSC的细胞活性及细胞增殖能力情况。结果 SPIO标记后SMSC经普鲁士蓝染色细胞质内可见蓝染颗粒,细胞标记率均达95%以上,且随着标记浓度的增高,细胞质蓝染铁颗粒增多,颜色加深。透射电镜下观察,细胞质及吞饮小泡内可见大量高电子致密度颗粒,呈阳性。在标记液浓度为（12.5~50）μg/ml时,标记后的细胞增殖能力与细胞活力与标记前比较无明显差别;当标记液浓度为100μg/ml以上时,细胞增殖能力与细胞活力受到抑制。结论根据初步研究,一定浓度范围的SPIO标记兔SMSC是安全可行的,为解决SMSC在关节内的示踪问题具有重要意义。

Objective To investigate the feasibility and biological characteristics of synovial mesenchymal stem cells（ SMSCs） labelled by superparamagnetic iron oxide（ SPIO）. Methods The rabbit SMSCs were isolated,cultured,purificated and identified in vitro. After adding the SPIO-labelled liquid,the cells were incubated 24 h in 37 ℃ carbon dioxide incubator. The lablled-cell samples were observed by Prussian blue staining,transmission electron microscope（ TEM） and the cell biology before and after the labeling was compared. Results The blue stained particles could be seen in the cytoplasm; the SPIO label was positive in 95% SMSC cells. With the concentration of the label liquid increasing,the blue-stained cytoplasm became darker. A large number of high electron density particles could be seen in the cytoplasm and in the pinocytosis vesicles by TEM,which suggested SPIO label positive. When the SPIO concentration was（ 12. 5 ~ 50） μg / ml,the differences in cell proliferation and cell viability between the SMSCs after labelling and the SMSCs before labelling were not significant; when the concentration was over 100 μg / ml,the cell proliferation and cell viability were inhibited. Conclusion A certain concentration range of SPIO can safely label the rabbit SMSC according to this study,which is important for tracing SMSCs in the joints.