^(99m)Tc螯合两种抗肝癌单链抗体的标记条件  

Radiolabeling of 2 kinds of single chain antibodies of anti-hepatocellular carcinoma with ^(99m)Tc

作　　者：王军伟[1] 师建国[1] 汪静[2] 舒博学 刘彦仿[1] 

机构地区：[1]第四军医大学基础部病理学教研室,陕西西安710033 [2]第四军医大学西京医院核医学科,陕西西安710033 [3]西安市高新医院核医学科,陕西西安710075

出　　处：《第四军医大学学报》2006年第15期1391-1394,共4页Journal of the Fourth Military Medical University

摘　　要：目的:研究两种全新的抗肝癌基因工程单链抗体hdsFv和scFv-PE38的99mTc标记方法及适宜条件以应用于放免显像.方法:选用二乙烯三胺五乙酸环酐(cDTPAa)作为螯合剂,沿用比较成熟的标记方法,以标记率和标记物免疫活性为指标分别测定两种单链抗体与99mTc偶联的适宜条件,并测定标记物的比活度和体外稳定性.结果:其他理化条件不变,cDTPA与hdsFv的浓度比为20∶1~40∶1,99mTc活度37~148MBq时,hdsFv标记率为62%~84%;cDTPA对scFv-PE38的浓度比为20∶1~100∶1,99mTc活度为37~148 MBq时,scFv-PE38标记率为68%~89%;且两种标记单链抗体的免疫活性均在60%以上.结论:通过对这两种全新的单链抗体的标记和检测,得到了尽可能保持其原有免疫活性的标记条件,为通过放免显像在活体内检验单链抗体亲瘤性奠定了基础.AIM： To study the methods and the conditions of labeling the 2 kinds of single chain antibodies （hdsFv, scFv- PE38） of anti-hepatocellular carcinoma with 99mTc. METHODS ： Choosing cyclic diethylenetriaminepentaacetic acid （cDTPA） as chelating agent and using the labeling methods on the basis of traditional approaches, eventually the optimal conjugate conditions between antibodies and cDTPA were determined. The immunoactivities of 99mTc labeled single chain antibodies were verified by linear extrapolation to binding at specific antigen excess. Finally the labeled compound was identified by specific activity and stability in vitro. RESULTS： The appropriate molar ratio of cDTPA to Ab ranged from 20：1 to 40：1 （hdsFv） and 20：1 to 100 ： 1 （scFv-PE38） , and the activity of 99mTc-pertechnetate, prepared for labeling was both from 37 MBq to 148 MBq. Under these conditions, the labeling efficiency of hdsFv was 62% - 84% , of scFv-PE38 was 68% - 89% , and the results of immunoactivities of labeled antibodies were above 60% （ P 〈 0.05 ）. CONCLUSION：We got the optimal labeling methods of these 2 single chain antibodies chelated with 99mTc. They kept both antibody＇s bioactivity and labeling efficiency farthest, which offered an available agent for radioimmunoimaging.

关 键 词：单链抗体 99mTc 同位素标记 金属螯合剂 肝肿瘤 

分 类 号：R817.9[医药卫生—影像医学与核医学]