LyP-1标记超顺磁性氧化铁的制备及体外成像

摘要

Objective To explore the feasibility of in vitro MR imaging of LyP-1-conjugated superparamagnetic iron oxide (SPIO) targeted breast cancer cells. Methods The coprecipitation method was employed to prepare SPIO. SPIO was coated with 3-aminopropyltrimethoxysilane (APTMS) and conjugated with LyP-1. The experiment was performed in LyP-1- SPIO group, competition group, SPIO group and control group, respectively. The distribution of iron in MDA-MB-231 cells was evaluated with Prussian blue stain under microscope. MTT assay was used to detect the cell viability, and in vitro MRI was performed. Results The preparation of SPIO was successful. The Prussian blue staining showed that there was significant intracellular accumulation of iron particles in the LyP-1-SPIO group, in comparison with sparse iron particle in the competition group and SPIO group. No intracellular iron particle was observed in the control group. MTT results did not reveal interference in the growth of MDA-MB-231 cells treated with LyP-1-SPIO or SPIO. In vitro MRI showed that LyP-1-SPIO significantly enhanced the negative contrast effect. Conclusion LyP-1-SPIO has effective targeting ability to the MDA-MB-231 cells and could be a useful probe for MRI diagnosis of breast cancer.%目的 探讨LyP-1标记超顺磁性氧化铁(SPIO)与乳腺癌细胞结合进行体外成像的可行性.方法 以共沉淀法制备SPIO,用LyP-1与3-氨丙基三甲氧基硅烷(APTMS)包被的SPIO耦联,以乳腺癌MDA-MB-231细胞株为研究对象,设立LyP-1-SPIO组、竞争组、SPIO组和对照组,普鲁士蓝染色,评价不同组中铁颗粒在细胞中的分布情况,四甲基偶氮唑盐(MTT)比色法检测细胞活性并观察其体外MR成像效果.结果 成功制备SPIO.LyP-1-SPIO组有较多铁颗粒进入细胞内,竞争组和SPIO组仅有少量铁颗粒进入细胞中,对照组细胞中无铁颗粒.MTT比色法检测结果显示不同作用时间LyP-1-SPIO和SPIO对细胞的生长均无显著影响;体外MR成像提示LyP-1-SPIO能够显著增强阴性对比效果.结论 LyP-1-SPIO对MDA-MB-231细胞具有较好的靶向作用,可用于对肿瘤细胞的影像学诊断.