188Re-CEA人/鼠嵌合抗体在裸鼠人结肠癌模型中的定位研究

目的 :评价1 88Re标记抗CEA人 鼠嵌合抗体在人结肠癌裸鼠模型中的肿瘤靶向性。方法 :于裸鼠尾静脉注入1 88Re CEA人 鼠嵌合抗体后 2 4、4 8、72、96h分别测定荷瘤小鼠体内组织放射性分布 ,于不同时相分别对尾静脉注射1 88Re CEA嵌合抗体及1 88Re C5 0鼠单抗的裸鼠行放免显像。结果 :1 88Re CEA嵌合抗体注射后 9 5h ,肿瘤部位开始有放射性浓聚。以后随时间的增加 ,肿瘤部位放射性持续存在并维持较高水平 ,而周围组织放射性逐渐清除。1 88Re CEA人 鼠嵌合抗体与1 88Re C5 0抗体一样在肿瘤中有很高的摄取。肿瘤组织在注射1 88Re CEA人 鼠嵌合抗体 2 4h后 ,摄取放射性占总注入量的百分比为11 0 5 % ,随时间的延长稍有增加。 96h时所有脏器T NT比均大于 2 0。结论 :1 88Re CEA人 鼠嵌合抗体可特异地浓聚于结肠癌组织 ,有望用于临床诊断和治疗。

Radiodetection of 188Re labeled chimeric anti-carcinoembryonic antige n antibody in nude mice bearing human colon carcinoma xenografts

Objective:To evaluate the tumor targeting properties of 188 Re labeled chimeric anti carcinoembryonic antigen(CEA) antibody ( 188 Re chi CEA) in nude mice bearing human colon carcinoma xenografts.Methods:The biodistribution was done at 24,48,72 and 96 hours following the injection of 188 Re chi CEA per nude mouse.Radioimmunoimaging was taken using a garmma camera on different interval after the injection of 188 Re chi CEA and 188 Re C50.Results:In radioimmunoimaging study,clear and rapid tumor imaging was obtained 9.5 hours after administration of 188 Re chi CEA.In comparative radioimmunoimaging studies,the tumor uptake of 188 Re chi CEA was the same as 188 Re C50.Statistics indicated the %ID/g in the tumor was 11.05% at 24 h after injection and showed only a minor increase thereafter.All tumor/normal tissue ratios are more than 2.0 at 96 hours after administration.Conclusion:These results suggest that 188 Re chi CEA can be specifically localized in the tumor of nude mice bearing human colon carcinoma.It is a potential radiopharmaceutical agent for the imaging and therapy for colorectal cancer.