摘要
目的:研究125I标记抗人CD40单克隆抗体(mAb)5H6同卵巢癌细胞HO8910体外结合的生物学特性以及在荷瘤鼠体内的分布和放射免疫显像。方法:氯胺-T法进行mAb 5H6 125I标记(125I-5H6),Lindmo法计算125I-5H6的免疫活性分数;细胞结合饱和实验进行Scatchard分析计算解离常数Kd及最大结合位点数Bmax;建立荷人卵巢癌(HO8910)裸鼠模型,分析125I-5H6在体内的分布,并用SPECT进行放射免疫显像。结果:mAb 5H6标记率为(85.4±5.2)%,放射化学纯度为(99.2±0.5)%,125I-5H6免疫活性分数为(38.6±5.4)%,与HO8910细胞的亲和力Kd=(0.711±0.06)nmol/L。在荷瘤鼠体内特异性结合HO8910肿瘤,48小时达到高峰,放射免疫显像肿瘤清晰可见。结论:125I-5H6同卵巢癌HO8910细胞在体外结合具有很高亲和力,在体内能特异性结合HO8910肿瘤,能获得优质的放射免疫图像。
Objective： To investigate in vitro binding properties of Iodine-125-Iabeled anti-human CD40 monoclonal antibody 5H6（125^I- 5H6） to HO8910 cells and to evaluate its biodistribution and imaging characteristics of planar gamma camera in ttanor-bearing mice. Methods： The mAb 5H6 was labeled with Nal125^I using chloramine-T method. Binding fraction of the labelled McAb was calcttlated by Lindmo Scheme. Both dissociation constant（Kd） and the maximal binding value （Bmax） were measured by binging saturation analysis. The stability, binding specificity and affinity of 125^I-5H6 were investigated with HO8910 ovary carcinoma cells as the target in vitro. Biodistribution and tumor-targeting characteristics of 125^I-5H6 were studied in BALB/c nude mice bearing an ovary tumor （ HO8910）. Planar gamma imaging illustrated the potential use of 125^I- 5H6 probe for radioimmunodetection. Results：Labeling efficiency of 1125^I-5H6 was （85.4± 5.2）% and its radiochemical purity was （99.2 ±0.5）% with suitable stability in vitro. At 4℃ ,the Kd for 125^I-5H6 binding to HO8910 cells was （0.711±0.06） nmol/L and immunoreactivity of 125^I-5H6 was （38.6± 5.4） % .125^I-5H6 targeted HO8910 cells with high specificity in vivo. Radioisotope uptake peaked at 48 hours for the tumor. Via planar gamma camera imaging, aanors could be clearly visualized. Conclusion： The affinity of 125^I-5H6 with HO8910 cells was high enough for detection in vitro and 125^I-5H6 can target the tumor with high specificity in vivo. Via planar gamma camera imaging,125^I-5H6 could provide good radioimmunoimages.
出处
《中国免疫学杂志》
CAS
CSCD
北大核心
2008年第6期533-537,共5页
Chinese Journal of Immunology
基金
国家自然科学基金资助项目(30571690)
国家863高新技术项目(2006AA02A254)
教育部博士点专项基金项目(20050285014)资助
