【作者】 季顺东；

【导师】 阮长耿；

【作者基本信息】 苏州大学 ， 内科血液学， 2004， 硕士

【摘要】 一、用2-IT法修饰SZ-51制备^99mTc标记血栓显像药盒 目的:研究^99mTc标记抗P-选择素（P-Selectin）单克隆抗体SZ-51血栓显像药盒的制备方法。方法:用2-亚氨基噻吩盐酸盐（2-IT）修饰SZ-51,用^99mTc-GH转换络合法标记IT-SZ-51,测定标记物的放化纯度及生物活性,以最佳标记条件制备血栓显像药盒。结果:以最佳比例修饰SZ-51,每分子抗体游离巯基数为13个,纸层析法测得标记率为90%以上,ELISA结果表明基本保留了抗体的免疫活性。制成的药盒4℃条件下可保存3个月以上。结论:该标记方法简便快速,为^99mTc-IT-SZ-51用于血栓放射免疫显像奠定了基础。 二、^99mTc-SZ-51对犬肺栓塞模型显像研究 目的:研究^99mTc-SZ-51对犬肺栓塞模型的显像效果。方法:用2-亚氨基噻吩盐酸盐（2-IT）修饰SZ-51,^99mTc-GH转换络合标记法标记IT-SZ-51后,对8只犬肺栓塞模型进行了放射免疫显像。结果:纸层析法测得标记率为90%以上,ELISA表明抗体保留了免疫活性。注入显像剂1小时后血栓部位开始显影并逐渐清晰,3小时后,在体显像及离体显像两者的放射性比值分别为5.3±0.5和7.0±1.2,形成1天的新鲜血栓的放射性摄取明显高于形成一周的血栓,离体组织测定两者比值达2.65。结论:^99mTc-SZ-51能够特异地浓集于犬肺肺栓塞部位,对显示肺栓塞的形成及鉴别新鲜与陈旧血栓具有一定的应用价值。 三、^99mTc-SZ51-F（ab）₂的制备及犬肺栓塞显像研究 目的:应用^99mTc标记抗人P-选择素（P-Selectin）单克隆抗体SZ51-F（ab）₂进行犬肺栓塞模型显像,观察其在检测肺栓塞及鉴别新鲜和陈旧血栓中的作用。方法:用预激活木瓜蛋白酶法制备SZ51-F（ab）₂,以2-亚氨基噻吩盐酸盐（2-IT）修饰后,采用^99mTc-GH转换络合标记法制备^99mTc-SZ51-F（ab）₂。以快速薄层层析法、酶联免疫吸附法（ELISA）测定标记物的标记率及生物活性。对4只犬肺栓塞模型进行了放射免疫显像。结果:SZ51-F（ab）₂的得率为46.7%,标记率为更多还原

【Abstract】 1. Preparing a kit of ^99mTc-labeled anti-P-Selectin McAb （SZ51）for radioimmunoimaging of thrombiObjective To establish a new method for preparing a kit of ^99mTc-labeled anti-P-Selectin McAb （SZ51） for radioimmunoimaging of thrombi. Methods SZ51 was modified with 2-iminotholane and labeled with ^99mTc-GH. Labeling yield, radiochemical purity and immunoreactivity were determined by ITLC-SG, Sephadex G-25 column chromatography and ELISA, respectively. The kit was prepared in the best label conditions. Results The McAb was modified at the best ratio, and the number of free thiol groups per antibody molecule was 13. The radiolabeling rate was 90%⁹5%. The results of ELISA showed that antibody reactivity was not affected. The stability of the kit could be maintained at 4℃ for more than 3 months. Conclusion The labeling method using a commercial kit is relatively simple and quick. ^99mTc-SZ51 could be a useful tool agent for imaging diagnosis of thrombotic disease.2. Preparation of ^99mTc -labeled SZ51 for radioimmunoimagingin dogs with pulmonary embolismObjective To evaluate the value of ^99mTc-SZ51 in detecting pulmonary embolism and distinguishing the fresh and old thrombi. Methods SZ51 was modified with 2-iminotholane and labeled with ^99mTc-GH. Labeling yield, radiochemical purity and immunoreactivity were determined by ITLC-SG, Sephadex G 25 column chromatography and ELISA, respectively. The 8 dogs with pulmonary embolism were used for radioimaging. Results Using the best ratio modified McAb, 90%⁹5% radiolabeling yield was obtained. The results of ELISA showed that antibody reactivity was not affected. Radioimaging results showed that ^99mTc-SZ51 concentrated in the pulmonary embolism 1 hour after injection, and more clearly gradually within 3 hours.Quantitative analysis showed the ratios of radioactive uptake between the thrombus and surrounding lung were 5.3±0.5 in vivo imaging and 7.0±1.2 in vitro. The higher uptake was found in fresh pulmonary thrombus than in old thrombus, the ratio of them was 2.65. Conclusion 99mTc-SZ51 was an available imaging agent for detecting experimental pulmonary embolism and distinguishing the fresh and old thrombus.3. Imaging experimental pulmonary embolism in dogs using99mTc-labeled SZ51-F（ab）2Objective Using 99mTc-labeled F（ab）2 fragment of anti P-selectin monoclonal antibody （McAb） SZ51 to image experimental pulmonary embolism in dogs and to assess its value in distinguishing the fresh from old thrombi. Methods SZ51-F（ab）2 fragment was prepared from McAb SZ51 using pre-activated papain digestion and then modified with 2-iminotholane and labeled with 99rTTc-GH using ligand exchange method. Labeling yield and immunoreactivity were determined by instant thin-layer chromatography （ITLC） and enzyme linked immunosorbent assay （ELISA）, respectively. Four dogs with pulmonary embolism were used for imaging. Results The yield of F（ab）2 fragment was 46.7% and radiolabeling yield was 90%⁹5%. As shown in ELISA, radio-labeled antibody retained P-selectin binding activity. One hour following intravenous injection of 99nTc-SZ51-F（ab）2, the agent appeared in the pulmonary embolism and became more clearly within 3 hours. The ratio of radioactive uptake between the thrombus and surrounding lung at 3 hours was 2.7±0.5. The uptake in fresh pulmonary thrombus （1 day old ） was higher than that in old thrombus （7 day old）, and the ratio of them was 2.47. Conclusion 99mTc- SZ51-F（ab）2was an available imaging agent for detecting pulmonary embolism and distinguishing the fresh and old thrombus.更多还原