叶酸介导超顺磁性氧化铁纳米颗粒标记舌癌细胞的磁共振成像研究

MRI study of human tongue cancer cell by using folate mediated superparamagnetic iron oxide nanoparticles

目的探讨叶酸(FA)介导的超顺磁性氧化铁纳米颗粒(PEG-PCL-SPIO)对于人舌癌细胞Tca-8113的靶向性及磁共振成像(MRI)的可行性。方法制备PEG-PCL-SPIO探针及FA靶向修饰的探针PEG-PCL-FA-SPIO,通过MTT试验验证其细胞毒性,并分别用PEG-PCL-SPIO(非靶向组)、PEG-PCL-FA-SPIO(靶向组)与人舌癌细胞Tca-8113(1×106)共同培育0.5、1、2 h后做细胞悬液的MRI检查,测量横向弛豫时间(T2值)变化。采用普鲁士蓝染色观察SPIO进入细胞内的情况。结果 MTT比色试验培养液中不同浓度的PEG-PCL-FA-SPIO的细胞活性,各组间的差异无统计学意义(F=0.698,P=0.676)。两种探针分别与Tca-8113细胞培育后0.5、1、2 h后MRI检查,两组细胞悬液的T2加权成像信号均下降,以2 h后更明显,靶向组在各时间段T2值下降的百分比均高于非靶向组(F=518.064,P=0.000)。普鲁士蓝染色显示,两种标记的细胞内均可见蓝色颗粒,靶向组中的蓝色颗粒比非靶向组的蓝色颗粒更多。结论 PEG-PCL-FA-SPIO对Tca-8113细胞有良好的靶向性,对舌癌的早期诊断具有重大应用潜力。

Objective To explore the feasibility of the human tongue cancer cell（Tca-8113）targeting and magnetic resonance imaging（MRI） abilities of the folate mediated superparamagnetic iron oxide nanoparticles（PEG-PCL-FA-SPIO）. Methods Both PEG-PCL-SPIO probes and PEG-PCL-FASPIO probes with folate targeted modification were prepared. The cytotoxicity of PEG-PCL-FA-SPIO was verified through MTT assay. Tca-8113 cell（1 × 10^6） were cultured with PEG-PCL-SPIO（non-targeting）and PEG-PCL-FA-SPIO（folate targeting）, respectively. Each group underwent MRI scan after cultured for 0.5, 1, 2 h, and the relative T2 values were recorded. Endocytosis of SPIO was observed through prussian blue staining. Results The cell viability of PEG-PCL-FA-SPIO in different concentrations showed no statistical difference according to the MTT assay（F = 0.698, P = 0.676）. Both the two probes were cultured with Tca-8113 cells for 0.5, 1, 2 h, respectively and the MRI demonstrated decreased T2 WI signal intensity of both groups, especially at 2 h. The folate targeting group showed a more significant decrease of relative T2 value at each time point（F = 518.064, P = 0.000）. Intracellular blue particles were observed in both groups after prussian blue staining, and the particles in folate targeting group were more than that of the non-targeting group. Conclusion PEG-PCL-FA-SPIO has favourable Tca-8113 cell targeting ability, and shows great potential in the early diagnosis of tongue cancer.