抗人胰腺癌细胞单克隆抗体SZ-121的放射免疫显像实验研究

目的研究^99mTc标记抗人胰腺癌单克隆抗体SZ-121在荷人胰腺癌裸鼠体内的显像及生物分布,探讨其用于胰腺癌早期诊断的可行性。方法采用皮下种植法建立荷人胰腺癌裸鼠移植瘤模型,以2-亚氨基噻吩盐酸盐（2-IT）修饰SZ-121,^99mTc-葡庚糖酸钠（GH）配体交换法标记SZ-121,经裸鼠尾静脉注入^99mTc-SZ-121后1、4h对裸鼠进行γ显像,于24h测定荷瘤小鼠体内组织的放射性分布。结果γ显像及生物分布显示,^99mTc-SZ-121被静脉注入荷瘤鼠后1h,肿瘤即清晰显影,随时间延长趋于增浓,且瘤组织与非瘤组织的放射性比值（T/NT）也逐渐增高,肿瘤每克组织百分注射剂量率（%IDPg）均高于注射^99mTc-IgG的对照组（P〈0.05）。结论^99mTc-SZ-121具有活体内定位导向能力,显像时间短,可能是一种有前途的胰腺癌显像剂。

Study on Image of Human Pancreas Carcinoma Xenografts with 99mTc Labeled Anti-pancreatic Cancer Monoclonal Antibody SZ-121

Objective To study the image and biodistribution of ^99mTc labeled anti-pancreatic cancer monoclonal antibody （McAb） SZ-121 in human pancreas carcinoma xenografts, and to develop new technology for early diagnosis of pancreas carcinoma. Methods The McAb SZ-121 was labeled with ^99mTc using 2-iminothiolane modification and ^99mTc-glucoheptonate （GH） transchelation method. The images were taken using T scintigraphy 1,4 h after injection, and the distribution 24 h after injection of ^99mTc- SZ-121 was observed. Results Clear tumor image was obtained 1 h after injection of ^99mTc-SZ-121. The radioactivity in the tumor and the radioactivity ratio of tumor to non-tumor tissue increased as time passing by. The %IDPg of tumor tissue in experiment group was higher than that in the control group at the 24 th h （P〈0.05）. Conclusion ^99mTc-SZ-121 has a capacity of in vivo oriented positioning, imaing time is short. So it perhaps is a promising pancreas carcinoma imaging agent.