结肠癌荷瘤裸鼠三步法预定位放免显像及导向治疗研究  

Experimental study of three-step pretargeting radioimmunoimaging and radioimmunotherapy in nude mice bearing human colon carcinoma

作　　者：李贵平[1] 朱承谟[2] 

机构地区：[1]第一军医大学南方医院核医学科,广东广州510515 [2]上海第二医科大学瑞金医院核医学科,上海200025

出　　处：《中国医学物理学杂志》2002年第3期129-131,136,共4页Chinese Journal of Medical Physics

基　　金：广东省医学科学技术研究基金(A2000389)

摘　　要：目的:探讨亲和素-生物素系统在人结肠癌裸鼠模型中进行预定位放免显像及导向治疗的实验研究。方法:应用三步法给药,在注药后4～48h对荷人结肠癌进行ECT显像和体内分布测定。预定位治疗组采用单次较大剂量投入治疗(放射性剂量为11.1MBq),治疗前后定期测量裸鼠的体重和肿瘤生长体积以及瘤块的组织病理学检查。结果:三步法组在注药后4h肿瘤即显像,其瘤/血比值为5.76±1.64明显高于对照组(直接标记法组和153Sm-DB2组分别为0.26±0.08和1.01±0.22)。三步法预定位治疗组与直接标记单抗组均能明显抑制荷瘤裸鼠体内人结肠癌的生长。结论:三步法预定位具有显著改善血T/NT比值,肿瘤显像时间提前的特点;预定位治疗具有明显的肿瘤抑制效应。Purpose:The aims of this study were to evalu ate three-step pretargeting technique of avidin-biotin system for ra-dioimmunoimaging and radioimmunotherapy in nude mice bearing human colon carcinoma.Methods:bi otinylated anti-CEA McAb was first injected followed by avidin48h and then 153 Sm-DB 2 24h after.SPECT imaging was performed and biodis tri-bution study was also performed at4h to48h post-injection.Groups of nude mice subcuta neously grafted with humancolon carcinoma were treated3days after the graft with a relatively high dose of11.1MBq.Toxicity was evaluated by change of body weight,and efficacy by variation in tumor volume.Histological analysis of tumors were performed.Results:With three-step pre targeting tech nique,the tumor was clearly visualized at4h inγ-imaging and at this time point tumor /blood pool ra tio was5.76±1.64,while for control group were0.26±0.08and1.01±0.22,respectively.Three-step pretargeting and 153 Sm-CEA McAb had a significant anti-tumor efficacy,and a high natural survival rate and a prolonging average sur vival time.Conclu sions:Three-step pretargeting technique can elevate the T/NT ratio and decrease the blood background.Earlier and better im ages can be ob tained using this technique.Three-step pretargeting radioimmunotherapy have a strong selective in-hibitory effect on colon carcinoma growth.

关 键 词：结肠癌 荷瘤裸鼠 三步法 预定位 导向治疗 放射免疫显像 

分 类 号：R735.35[医药卫生—肿瘤]