^(99m)Tc-EGFR-McAb用于荷人肺腺癌裸鼠的放射免疫显像研究

Application of ^(99m)Tc-EGFR-McAb to radioimmunoimaging for nude mice bearing human lung adenocarcinoma

目的:评价99mTc标记的表皮生长因子受体(Epidermal growth factor receptor,EGFR)单克隆抗体(Monoclone antibody,McAb)用于荷人肺腺癌裸鼠的放射免疫显像(Radioimmunoimaging,RII)效果,并进行相关比较分析。方法:①建立荷人肺腺癌裸鼠动物模型;②采用99mTc直接标记法标记抗EGFR的单克隆抗体,并对标记抗体的特性进行鉴定;③利用99mTc-EGFR-McAb进行荷人肺腺癌裸鼠模型的RII及体内分布研究。结果:99mTc对EGFR-McAb的标记率为91.5%±3.8%,标记抗体比活度为(2.8±0.2)MBq/μg,放射化学纯度为96.5%±3.2%。放射免疫显像结果显示,99mTc-EGFR-McAb对肿瘤组织有较高的亲和性,通过感兴趣区(Regional interest,ROI)技术测得T/NT比值为2.74±0.5,明显高于对照组(P<0.05)。标记抗体的体内分布结果与显像结果基本一致。结论:99mTc-EGFR-McAb用于荷人肺腺癌裸鼠的放射免疫显像能得到较理想的靶/非靶比值,EGFR是肺腺癌放射免疫显像研究值得推荐的目标抗原。

Objective：To evaluate of the application of 99m Tc-EGFR-McAb to radioimmunoimaging for nude mice bearing lung adenocarcinoma and do correlation analysis.Methods：① The model of nude mice bearing lung adenocarcinoma was established;②The direct labeling method of 99mTc was applied to labele monoclonal antibodies for EGFR,and then the properties of the labeling antibodies were identified;③Radioimmunoimage and radioactivity distribution with 99mTc-EGFR-McAb on the animal model of nude mice bearing lung adenocarcinoma were studied.Results：The labeling rates of 99mTc for EGFR-McAb was 91.5% ±3.8%.Specific activity of the labeled antibody was（2.8±0.2）MBq/μg,and the radiochemical purity was 96.5%±3.2%.The tumor had high intake of the labeled antibodies according to radioimmunoimaging result.The T/NT relative value measured through ROI technique was 2.74±0.5,which was significantly higher than that of the control group（P〈0.05）.The body distribution results of the labeled antibodies and their imaging results were basically identical.Conclusion：The ideal target and non-target ratios could be obtained by applying 99mTc-EGFR-McAb to radioimmunoimaging of nude mice bearing lung adenocarcinoma,and EGFR may be an ideal target antigen to lung adenocarcinoma in the radioimmunoimaging study.