新型染料IR-808靶向肿瘤近红外荧光成像的体内研究

目的 探讨近红外荧光染料IR-808在移植瘤动物模型中特异性的肿瘤靶向示踪作用。方法建立人肺癌细胞系NCI-H460、结肠癌细胞系HCT-116及鼠源肝癌细胞系Hepa 1-6皮下移植瘤裸小鼠模型，未接种癌细胞的裸小鼠作对照。尾静脉注射同等剂量染料IR-808，分别在不同时间点对裸小鼠正常组织及肿瘤组织进行近红外荧光成像，追踪染料在裸小鼠体内的分布，评价其肿瘤靶向作用。结果 在未接种的裸小鼠体内，IR-808染料首先在肝脏、心脏聚集，随后信号减弱，48h后基本代谢排出体外；在荷瘤裸小鼠模型体内，IR 808染料注入24h后开始靶向肿瘤，72h后荧光信号仍很稳定；取荷瘤裸小鼠组织进行近红外荧光成像，发现仅肿瘤组织有信号，其他组织无信号。全部实验小鼠状态良好，未见明显毒性反应。结论 近红外荧光染料IR 808能特异性靶向肿瘤成像，且信号稳定，无明显毒性，具有重要的应用前景

Tumor targeting study of new dye IR-808 by near-infrared fluorescence imaging in vivo

Objective To study the tumor targeting properties of near-infrared（NIR） fluorescence dye IR-808 in tumor xeno- grafts by in vivo optical imaging system. Methods Human lung cancer cell line （NCI-H460） , human colon cancer cell line （ HCT- 116） and murine hepatoma cancer cell line （Hepa 1-6 ） were established as subcutaneous tumor xenografi models by injection into BAlB/C-nu/nu female nude mice with 3 x 106 （ NCI-H460 and HCT-116 ） and 2 x 105 （ Hepa 1-6）. Meanwhile, mice that had not been injected with cancer cells were used as control. Normal and tumor tissues were subjected to NIR imaging at different time points after iv injection of IR-808 at the same dose. The distribution and tumor targeting effect of the dye were observed successively in vivo. Results The preferential organs for uptake and retention of the dye were liver and heart in normal mice and the dye was basically ex- creted after 48h. The NIR signal started to condense in tumor at 24h after dye injection and was still stable after 72h in tumor xeno- grafts. Dissected organs were subjected to NIR imaging, and the fluorescence signal was only found in tumor. The mice were in good status without obvious systemic toxicity. Conclusion Near-infrared fluorescence dye IR-808 can specifically target on tumor with sta- ble signal and no obvious systemic toxicity, showing great application potential in future.