新型肿瘤靶向超顺磁氧化铁纳米粒在裸鼠头颈移植瘤MRI诊断中的实验研究

目的探讨叶酸-羧甲基壳聚糖-超顺磁氧化铁纳米粒（folic-acid o-carboxymethyl chitosans superamagnetic nanoparticle,FA-OCMCS-SPIO-NPs）在头颈移植瘤MRI诊断中的价值。方法雌雄各半的20只BACB/C裸鼠为动物模型,皮下种植KB细胞（人口咽癌细胞）4周后,建立KB细胞移植瘤模型,取荷瘤成功的16只裸鼠MRI平扫后,按数字随机法分为FA-OCMCS-SPIO-NPs组（实验组）和羧甲基壳聚糖-超顺磁氧化铁纳米粒OCMCS-SPIO-NPs（对照组）,每组8只。实验组尾静脉注射FA-OCMCSSPIO-NPs,对照组尾静脉注射OCMCS-SPIO-NPs,并进行MRI增强扫描。T2 WI图像比较增强前、后信号强度,结合HE和普鲁士蓝染色结果,评价FA-OCMCS-SPIO-NPs在头颈移植瘤诊断中的价值。结果实验组FA-OCMCS-SPIO-NPs增强前后,T2WI肿瘤区域信号强度较平扫信号降低27.23%,两者比较差异具有统计学意义（P=0.001）;肿瘤组织普鲁士蓝染色阳性,HE染色有大量散在SPIO聚集;对照组OCMCS-SPIO-NPs增强后,T2 WI肿瘤区域SI与平扫比较信号无明显下降（P〉0.05）,普鲁士蓝染色阴性,HE染色亦未见SPIO聚集。结论 FA-OCMCS-SPIO-NPs可以提高头颈肿瘤MRI诊断的准确性和可靠性,能够作为理想的对比剂而用于头颈移植瘤的MRI诊断。

Effect of a novel tumor targeting superparamagnetic iron oxide nanoparticle on MRI diagnosis of transplantation tumor of head and neck in nude mice

Objective To explore the effect of folic acid o carboxymethyl chitosans superamagnetic nanoparticle （FA OCMCS SPIO NPs ） on MRI diagnosis of transplantation tumor of head and neck in nude mice. Methods Twenty BALB/C nude mice, male and female in half, were chosen as model animal. KB cell line was inoculated subcutaneously into the mice. 4 weeks after inoculation, the animal model of transplantation tumor of head and neck was successfully established. 16 mice were randomly divided into two groups, i. e. , FA OCMCS SPIO NPs group （experimental group ） and OCMCS SPIO NPs group （control group ）. The mice of the experimental group were enhenced by injection of FA OCMCS SPIO NPs, while those of the control group by OCMCS SPIO NPs. MRI images were obtained before injection and 3 hours after injection sparately. The signal intense （ SI ） in the regions of interest （ROI） was determined on T2 weight image （T2WI）. Combined with HE and Prussian blue-staining images, the effect of FA OCMCS SPIO NPs on MRI diagnosis of transplantation tumor of head and neck was evaluated. Results T2WI imagines of the experimental mice showed that the average SI of ROI after injection was decreased by 27.23 % when compared with that before injection, and the difference was statistically significant （ P 〈 0.05 ）. The difference of SI in the control group was statistically insignificant （P 〉 0.05 ）. HE and Prussian blue staining of tumor tissue slice showed scatter SPIO NPs aggregation and positive Prussian blue staining only in the experimental group. Conclusion Via improving accuracy and reliability, FA OCMCS SP10 NPs can be used as an ideal MRI contrast agent for the MRI diagnose of head and neck tumor.