^99Tc^m—标记EGF受体单抗肺癌放免显像的实验研究

目的 研究^99Tc^m-标记表皮生长因子受体（EGFR）单克隆抗体（MAb)egf/r3在裸鼠体内的肺癌放射免疫显像（RII）。方法 ^99Tc^m标记的还原型抗体egf/r3尾静脉注入荷瘤裸鼠，于不同时间行系列显像，采用感兴趣区法计算各时相T／NT值。于注射药后30h处死动物、计算抗体的生物分布、T／NT及NT／B值。结果 标记率为99％、胶体放射性为3．87％，放射性比活度为348MBq/mg。注药后3h瘤块显像，15－25h达浓聚高峰，T／NT比值最高达4．59。除肝、脾及肾外，其他脏器放射性分布均较低。结论 ^99Tc^m-egf/r3显像时间早，T／NT比值高，图像清晰。

Lung cancer radioimmunoimaging using ~(99)Tc~m-labeled anti-epidermal growth factor receptor monoclonal antibody in nude mice

Objective To study Lung cancer radioimmunoimaging (RII) by using 99Tcm-labeled anti-epidermal growth factor receptor monoclonal antibody (EGFR-MAb) in nude mice.Methods (1) Preparation of human lung cancer cell line SPC-A1 xenografts bearing nude mice model. (2) Labeling of IgG2a MAb egf/r3 with 99Tcm. (3)Performing RII of the MAb on nude mice bearing xenografts. (4) Measuring of the Tumor/Non Tumor (T/NT) values in vivo using ROI technique and in vitro thirty hours after 99Tcm-egf/r3 administration.Results (1) The radiolabeled ratio was 99%, the colloid formation was 3.87%, specific activity was 348 MBq/mg. (2) Three hours after 99Tcm-egf/r3 administration ,the tumor images began to display , the best image displayed between fifteen and twenty five hours after the MAb administration. (3) Organ background was low except in liver,spleen and kidney.Conclusion RII with 99Tcm-egf/r3 MAb on nude mice bearing xenografts gave rather early and clear images of the tumor,and this provides the basis for application of 99Tcm-egf/r3 RII in the clinical diagnosis of lung cancer.