比较两种方法修饰的免疫磁性纳米探针在小鼠体内肿瘤磁共振成像中的作用

目的 评价两种免疫磁性纳米探针(Anti-Sp17-Silane@MNPs和Anti-Sp17-CS@MNPs)对小鼠体内肿瘤MRI的靶向效果.方法 分别将硅烷和壳聚糖修饰的磁性纳米粒与抗Sp17单克隆抗体交联,形成两种免疫磁性纳米探针(Anti-Sp17-Silane@MNPs和Anti-Sp17-CS@MNPs),对荷瘤裸鼠注射后进行MR扫描,并解剖实验鼠,取器官组织(肺、肝和肿瘤)进行普鲁士蓝染色,观察铁粒子聚集情况.结果 两种探针注射2 h后,肿瘤感兴趣区均可见T2信号明显降低,Anti-Sp17-CS@MNPs组降低更为显著.组织学检查见Anti-Sp17-Silane@MNPs注射组在肺、肝均有明显铁粒子聚集,而Anti-Sp17-CS@MNPs注射组各个器官组织铁粒子非特异聚集明显减少.结论 MRI中, 对于小鼠体内肿瘤,Anti-Sp17-CS@MNPs探针比Anti-Sp17-Silane@MNPs特异性更好.

Comparison of effect of two immunomagnetic nanoparticles on in vivo tumor MRI in nude mice

Objective To evaluate in vivo targeting effects of two immunomagnetic nanoparticles (Anti-Sp17-Silane @MNPs and Anti-Sp17-CS@MNPs) on tumor MRI in nude mice. Methods The anti-Sp17-Silane@MNPs and anti-Sp17-CS @MNPs were prepared with grafting anti-Sp17 antibodies on the surface of the magnetic nanoparticles using the linker of EDC/NHS (1-ethyl-3- carbodiimide/N-hydroxysuccinimide). The nude mice bearing hepatocellular carcinoma cell were divided into two groups and injected with anti-Sp17-Silane@MNPs and anti-Sp17-CS@MNPs, respectively. After injection of immunomagnetic nanoparticles, MR scan were performed. The nude mice were sacrificed after injected Anti-Sp17-MNPs, tissue samples (lung, liver and tumor) were stained with prussian blue, observing the aggregation of the iron. Results After injection of immunomagnetic nanoparticles, the decrease of T2 signal intensity in tumor was observed at 2 h. The decrease of T2 signal intensity of anti-Sp17-CS@MNPs group was more obvious. Anti-Sp17-Silane@MNPs were usually taken up in the lung and liver. However, Anti-Sp17-CS@MNPs in the lung and liver by non-specific absorption decreased obviously. Conclusion Anti-Sp17-CS@MNPs has more specific effect than anti-Sp17-Silane@MNPs on in vivo tumor MRI in nude mice.