超顺磁性氧化铁标记对大鼠骨髓间充质干细胞生物学特性的影响

In vitro study of rat mesenchymal stem cells labeled with superparmagnetic iron oxide

目的:探讨超顺磁性氧化铁(SPIO)标记骨髓间充质干细胞(MSCs)的方法、效果及其对MSCs生物学特性的影响。方法:用密度梯度离心加贴壁培养法分离、扩增大鼠MSCs。取第4代MSCs,用终浓度为25μgFe/mL的SPIO-多聚赖氨酸(PLL)复合物进行标记。标记后动态观察MSCs的形态改变,用台盼蓝染色检测细胞的活力,MTT比色法检测细胞增殖能力,普鲁士蓝铁染色证实细胞内铁,分光光度法测定细胞铁含量。结果:MSCs的SPIO-PLL标记阳性率达100%,标记后的MSCs细胞内铁含量为(18.38±2.80)pg/cell,是未标记细胞的76倍。标记细胞的形态、活力、生长增殖能力与未标记细胞相比无明显改变。结论:PLL介导SPIO标记MSCs方法简便、效率高,不影响MSCs的生物学特性,可用于MSCs的标记和示踪。

Objective To evaluate the method and efficiency of labeling MSCs with SPIO-PLL, and evaluate the effect of SPIO-PLL-labeling on biological characteristics of MSCs. Methods MSCs cells were isolated from bone marrow of SD rat by density gradient centrifugation and adherent culture. The fourth generation MSCs were transfected with 25μg Fe/ml SPIO-PLL. Cell viability and proliferation were evalutated by the exclusion of trypan blue dye and MTF assay, respectively. The morphologic change of MSCs was dynamically observed by inverted phased microscope. Iron uptake via endocytosis was identified by prussian blue staining and quantified by spectroscopy. Results The percentage of iron-positive cells was 100% after 24 h incubation with SPIO-PLL. The iron load in SPIO-PLL-labeling cells was （ 18.38±2.80）pg/cell, which was 76-fold higher than that in unlabelled cells. Compared with unlabelled cells, neither cell viability nor proliferation of SPIO-PLL- labelling MSCs were obviously changed. Conclusions Labeling MSCs with SPIO-PLL is convenient and effective, without affecting the biological characteristics of MSCs , it should be a useful method for tracking MSCs.