^(99m)Tc-5-FU免疫纳米粒在荷人胃癌SCID鼠模型体内的分布  

Biodistribution of ～(99m)Tc-labeled Anti-VEGF mAb 5-FU loaded polylactic acid nanoparticles in human gastric carcinoma xenografts

作　　者：黄开红[1] 刘建化[1] 朱兆华[1] 李学先[1] 卢献平[2] 周淑英[1] 

机构地区：[1]中山大学附属第二医院消化疾病研究所,广东广州510120 [2]中山大学附属第二医院核医学科,广东广州510120

出　　处：《南方医科大学学报》2007年第8期1137-1140,共4页Journal of Southern Medical University

基　　金：国家自然科学基金(30670951);广东省自然科学基金(06021322);广州市科技攻关项目(2003Z3-E0381);广东省科技攻关项目(2005B31211002)~~

摘　　要：目的探索制备99mTc标记载5-FU抗VEGF单克隆抗体纳米粒(99mTc-5-FU-Ab-NPs)的方法,并观察99mTc-5-FU-Ab-NPs胃癌移植瘤模型体内的分布情况。方法用改进的Schwarz方法对载5-FU抗VEGF单克隆抗体纳米粒进行99mTc标记,经SephadexG250柱分离纯化,用纸层析法测定标记率与放化纯度;ELISA法和免疫组化法测定标记物的免疫活性;经荷人胃癌鼠静脉注射99mTc-Ab-5-FU-NPs(实验组)及99mTc标记鼠源性多克隆IgG纳米粒(对照组),并于2、6h行放射免疫ECT显像,用感兴趣区(ROI)技术获得实验组和对照组荷人胃癌鼠全身和肿瘤放射性计数及肿瘤与对侧正常组织(T/NT)的放射性比值;24h显像后处死鼠,测定体内放射性分布,计算每克组织百分注射剂量率(%ID/g)及T/NT比值。高效液相色谱法检测两组鼠肿瘤组织和血液中5-FU的浓度。结果制备所得99mTc-5-FU-Ab-NPs标记率为90%￣95%,抗体的活性在标记前后无明显下降;荷人胃癌鼠放射免疫显像结果提示静脉注射99mTc-5-FU-Ab-NPs 2h后肿瘤已显影,随时间延长到6h更清晰,2和6h肿瘤组织ID%/g均显著高于对照组;6h时实验组肿瘤组织ID%/g和肿瘤与血液的放射性比值较2h时升高;同时,实验组肿瘤组织中5-FU浓度随着时间延长呈持续升高且与对照组5-FU浓度相比有显著性差别。结论本研究制备所得99mTc-5-FU-Ab-NPs能较好地满足放射免疫显像的要求;抗VEGF单克隆抗体的免疫导向作用可靠,注射后6h,99mTc-5-FU-Ab-NPs在肿瘤组织中有相对较高的特异性浓聚。Objective To prepare 99mTc-labeled Anti-VEGF mAb 5-FU loaded polylactic acid nanoparticles （99mTc-Ab-5-FU-NPs） and investigate its biodistribution in human gastric carcinoma xenografts. Methods 99mTc-Ab-5-FU-N-Ps were prepared by labeling Ab-5-FU-NPs with 99mTc using improved Schwarz method. After isolation of 99mTc-Ab-5-FU-NPs using SephadexG250 column, the labeling ratio and radiochemical purity were determined using chromatography. The immunocompetence of 99mTc- Ab-5-FU-NPs was detected by ELISA and immunohistochemistry. 99mTc-Ab-5-FU-NPs were then injected via the tail vein into SCID mice bearing human gastric carcinoma, and 99mTc labeled mice-derived monoclonal IgG loaded polylactic acid nanoparticles were used as the control, followed by radioimmunoscintigraphic imaging at 2 and 6 h. The radioactive count and radioactive ratio of the tumor and non-tumor tissue （T/NT） in the animal models were calculated using ROI technique. After imaging at 24 h, SCID mice were sacrificed and the radioactive distribution, the %ID/g, as well as the T/NT radioactive ratio were examined, respectively. The concentrations of 5-FU in the tumor and blood were also detected using HPLC method. Results The labeling ratio of 99mTc-Ab-5-FU-NPs was 90%-95%. 99mTc-Ab-5-FU-NPs were detected in the tumor tissues by radioimmunoimaging 2 h after the injection. ID%/g in the tumor tissues at 2 and 6 h were both significantly higher than that of the control group. Both the ID%/g in tumor tissues and radioactive ratio of tumor and blood at 6 h were higher than those at 2 h, and the concentration of 5-FU in experimental group increased continuously with time and was significantly higher than that in control group. Conclusions 99mTc-Ab-5-FU-NPs prepared in this study can meet the demands of radioimmunoimaging, and the anti-VEGF monoclonal antibody possesses reliable immune targeting ability. Six hours after injection, 99mTc-Ab-5-FU-NPs can specifically accumulate in the tumor tissues in human gastric carcinoma xenografis at high concentrat

关 键 词：锝 胃肿瘤 单克隆抗体 纳米微粒 氟尿嘧啶 

分 类 号：R735.2[医药卫生—肿瘤]