分子探针^(131)I-ch4E5的制备及其动物实验研究  

Preparation of molecular probe 131I-ch4E5 and its animal experiment research

作　　者：罗阳子 邱玉华 张玉娜[1] 翟士军[1] Luo Yangzi;Qiu Yuhua;Zhang Yuna;Zhai Shijun(Department of Nuclear Medicine,People's Hospital of Shanghai Putuo District,Shanghai 200060,China;Department of Immunology,School of Medicine,Soochow University,Suzhou 215123,China)

机构地区：[1]上海市普陀区人民医院核医学科,上海200060 [2]苏州大学医学部免疫学系,苏州215123

出　　处：《国际放射医学核医学杂志》2022年第6期354-359,共6页International Journal of Radiation Medicine and Nuclear Medicine

摘　　要：目的探讨靶向B细胞淋巴瘤的分子探针131I-ch4E5的制备方法及其对荷人B细胞淋巴瘤裸鼠的抑瘤作用。方法采用Iodogen法用131I标记抗CD80的人-鼠嵌合抗体ch4E5,采用放射性薄层色谱扫描法测定标记率和放射化学纯度。(1)体外实验:在含细胞数为1×108、1×109、1×1010、5×1010、1×1011个/L的人B细胞淋巴瘤Raji细胞的离心管中分别加入131I-ch4E5溶液,同时设置非特异结合对照管,测量每管沉淀的放射性计数,计算Raji细胞与131I-ch4E5的特异性结合率。(2)体内实验:3只荷瘤裸鼠尾静脉注射7.4 MBq的131I-ch4E5,72 h后处死,分别取肿瘤、血等14种脏器或组织,分别计算肿瘤与正常组织的放射性比值(T/NT);将15只荷瘤裸鼠按随机数字表法分为3组,分别经尾静脉注射131I-ch4E5(131I-ch4E5组)、未标记的ch4E5(ch4E5组)及生理盐水(对照组),观察3组荷瘤裸鼠的肿瘤生长情况,给药后第15天计算肿瘤生长抑制率;之后处死荷瘤裸鼠取肿瘤组织,采用苏木精-伊红染色法做组织病理学检查。2组间的比较采用两独立样本t检验。结果 131I-ch4E5的标记率为(84.2±2.4)%、放射化学纯度为(97.1±1.1)%。(1)体外实验:131I-ch4E5与Raji细胞的结合率随细胞数量的增加而升高,最大结合率为(38.2± 2.3)%。(2)体内实验:131I-ch4E5在荷人B细胞淋巴瘤裸鼠体内的分布具有靶向性,肿瘤与肌肉的T/NT最大为7.30;与ch4E5组、对照组比较,131I-ch4E5组肿瘤生长减慢,差异均有统计学意义(t=2.889、6.516,均P<0.05);给药后第15天,131I-ch4E5组肿瘤抑制率为71.7%、ch4E5组为43.4%。组织病理学检查结果同样显示131I-ch4E5的治疗效果更明显。结论自制分子探针131I-ch4E5的标记率及放射化学纯度高,且对荷人B细胞淋巴瘤裸鼠肿瘤生长有明显的抑制作用,为进一步研究131I-ch4E5在放射免疫治疗中的应用提供了实验依据。Objective To investigate the preparation method of a molecular probe 131I-ch4E5 for targeting B-cell lymphoma and its anti-tumor effect in human B-cell lymphoma-bearing nude mouse model.Methods The anti-CD80 human-mouse chimeric antibody ch4E5 was labeled with 131I through the Iodogen method,and its labeling rate and radiochemical purity were determined by radioactive thin layer chromatography scanning method.(1)In vitro experiments:131I-ch4E5 solution was added to cytocentrifuge tubes containing 1×108,1×109,1×1010,5×1010,and 1×1011 cells/L of human B-cell lymphoma cells(Raji cells)and to non-specific binding control tubes.Radioactivity counts per tube of precipitation were measured to calculate the specific binding rate of Raji cells to 131I-ch4E5.(2)In vivo experiments:7.4 MBq of 131I-ch4E5 was injected into three tumor-bearing nude mice via the tail vein.After 72 h,the tumor-bearing nude mice were sacrificed.Fourteen organs or tissues,such as tumor and blood,were harvested and weighed,and their radioactivity was measured.The radioactivity ratio of tumor to normal tissue(T/NT)was calculated.In the treatment study,15 tumor-bearing nude mice were divided into three groups according to the random number table method and injected with 131I-ch4E5(131I-ch4E5 group),unlabeled ch4E5(ch4E5 group),and normal saline(control group)through the tail vein.Tumor growth was observed in the three groups.After 15 days,the tumor inhibition rate was calculated,and then the tumor-bearing nude mice were sacrificed to harvest tumor tissues for histopathological examination by hematoxylin-eosin staining.Comparisons between the two groups were performed using two independent samples t-test.Results The labeling rate of 131I-ch4E5 was(84.2±2.4)%,and the radiochemical purity was(97.1±1.1)%.(1)In vitro experiments:the binding rate of 131I-ch4E5 to Raji cells increased with increasing cell concentration,and the maximum binding rate was(38.2±2.3)%.(2)In vivo experiments:the distribution of 131I-ch4E5 in human B-cell lymphoma-bearing n

关 键 词：分子探针 碘放射性同位素 ch4E5 淋巴瘤 B细胞 放射免疫疗法 荷瘤裸鼠 

分 类 号：R733[医药卫生—肿瘤] R-332[医药卫生—临床医学]