抗癌胚抗原单链抗体与核心链霉亲和素融合蛋白在荷瘤裸鼠体内的预定位显像  

The biodistribution and pretargeting radioimmunoimaging of the fusion protein of anti-CEA single-chain antibody and core-streptavidin in human rectocolonic tumor bearing nude mice

作　　者：杨卫东[1] 李彪[1] 朱承谟[1] 江旭峰[1] 冯国伟[1] 吴祥甫[2] 

机构地区：[1]上海第二医科大学附属瑞金医院核医学科,200025 [2]中国科学院上海生物化学细胞研究所

出　　处：《中华核医学杂志》2002年第6期328-330,T001,共4页Chinese Journal of Nuclear Medicine

基　　金：国家自然科学基金资助项目 (39770 2 31 );上海市启明星计划资助项目 (98QB1 4 0 1 1 )

摘　　要：目的　研究1 53Sm 生物素和抗癌胚抗原单链抗体与核心链霉亲和素融合蛋白 (CEAScFv core streptavidin)在荷人结直肠癌裸鼠体内的两步法预定位显像和体内分布。方法　对 2 3只荷人结直肠癌裸鼠腹腔注射CEAScFv core streptavidin进行预定位 ,2 4h后腹腔注射1 53Sm 生物素 ,其中2 0只于 1、4、8和 2 4h进行体内分布研究 ,余 3只于 8和 2 4h进行定位显像。结果　在荷人结直肠癌裸鼠腹腔注射CEAScFv core streptavidin预定位后 2 4h ,注射1 53Sm 生物素后 1h ,肿瘤 血比值为 0 .4 9,4和 8h达 1.2 1和 1.5 6 ,2 4h达最高 ,为 3.0 9。裸鼠定位显像示 ,8h肿瘤部位放射性明显浓聚 ,2 4h本底明显降低 ,肿瘤呈放射性“热”区。结论　1 53Sm 生物素和CEAScFv core streptavidin预定位显像能提高靶 非靶比值 ,缩短显像时间 ,改善图像质量。ObjectiveTo investigate the biodistribution and two-step pretargeting radioimmunoimaging of the fusion protein of anti-carcinoembryonic antigen (CEA) single-chain antibody (ScFv) and core-streptavidin in human rectocolonic tumor bearing nude mice. MethodsBefore the injection of 153Sm-biotin, the fusion protein of ScFv-core-streptavidin was pretargeted for 24 h (200 μg every nude mouse), 24 h later 153Sm-biotin was injected. The uptake of radioactivity in tumor and normal tissues in 20 nude mice was measured at 1,4,8 and 24 h and the other 3 nude mice was scanned at 8 and 24 h after peritoneal injection of 153Sm-biotin. ResultsTBThe tumor to blood ratio ( tumor/blood) reached 0.49, 1.21, 1.56 and 3.09 at 1, 4, 8 and 24 h respectively. Radioactivity concentration peaked at 8 h in tumor site and demonstrated a 'hot' area, with significant decreasing its background at 24 h. ConclusionThe fusion protein can elevate the tumor/blood ratio, shorten pretargeting and imaging process and also improve image quality.

关 键 词：核心链霉亲和素融合蛋白 抗癌胚抗原单链抗体 结肠直肠肿瘤 重组融合蛋白质 放射免疫检测 动物实验 

分 类 号：R817.4[医药卫生—影像医学与核医学]