抗C-erbB-2单克隆抗体在荷人胃癌裸鼠体内的预定位显像

Radioimmunoimaging study using pretargeting system on^(153) Sm labeled anti- C-erbB-2 monoclonal antibody in nude mice grafted with human stomach carcinoma

目的以153Sm标记的抗C-erbB-2单克隆抗体对荷人胃癌移植瘤裸鼠进行肿瘤预定位显像的研究。为胃癌早期诊断提供一种新方法,并为其临床应用提供实验依据。方法实验Ⅰ组每只裸鼠预定位法从尾静脉注射7.4MBq/0.1ml实验Ⅱ组与Ⅲ组分别直接从尾静脉注射7.4MBq/0.1ml的135Sm-C-erbB-2及135Sm-IgG并于于注射后2、4、8、24h行全身SPECT显像。于4、8、24h分批处死裸鼠并测定分别在肿瘤、血液、心脏、肺等重要脏器单位重量的放射性比值(%ID/g)。结果在运用预定位技术加药的实验I组在给药后2h开始有抗体在肿瘤组织浓聚,在8h时达到最高,与实验Ⅱ组直接给予抗体比较,血液本底低,两组比较差异有显著性。(P<0.05)。结论应用预定位技术的实验组,瘤/血液比值高,血液本底低,周围正常组织吸收剂量低,显像效果好。

Objective To study using pretargeting system on radioimmunoimaging of^153 Sm labeled anti- C-erbB-2 monodonal an- tihody and normal mice IgG in nude mice witli human stomach careinonm and provide the basis for clinical use. Methods group I 3-step pretargeting injected into the tail vein with 7.4 MBg/0.1 ml labeled antibody, group Ⅱ and Ⅲ injected directly into the tail vein with 7.4 MBg/0.1 ml labeled antibody. SPECT were measured after 2,4,8,24 h interval of injection. Percent injected dosage of every gram tissue（ % ID/g） were measured after 4,8,24 h interval to death. Results The tumor to blood ratio reached 4.64,7.65,9. 44 at 2,4,8 hours respectively. Radioactivity concentration peaked at 8 h in tumor site. the tumor/blood was higher than153 Sm-C- erbB-2（ P 〈 0.05）. Conclusion pretargeting system on radioimmunoimaging improves the amounts of locatingon toumors and yields a specific enhancing effect and also improve image quality.