【摘要】 生物机体内天然存在许多受体与配体,它们之间亲和结合力远远高于抗体亲和力(K_d=10^-8～10^-9).本实验根据VEGFR和VEGF之间的高亲和力(K_d=1.6×10^-11),以新生血管细胞表面的VEGFR为靶点,设计VEGF-hFc融合蛋白作为靶向抗肿瘤药物.在本实验中构建pcDNA3.1-IgG leader-VEGF-hFc重组载体,转染CHO/dhFr^-细胞真核表达融合蛋白VEGF-hFc,并通过Protein A纯化.使用A549细胞构建人非小细胞肺癌裸鼠肿瘤模型,小鼠静脉注射10μg VEGF-hFc融合蛋白用以抗肿瘤研究.连续给药4次后,肿瘤生长曲线表明,与对照组相比,实验组小鼠的肿瘤生长得到明显的抑制甚至消退;数据统计显示,VEGF-hFc肿瘤抑制率达90%.更多还原

【Abstract】 There are lots of endogenous ligands and receptors,such as VEGF and VEGFR,whose affinity (K_d=1.6×10^-11)is about 100 folds higher than that of antibody drugs(K_d=10^-810^-9).Based on the high affinity of between VEGFR and VEGF,a fusion protein VEGF-hFc was designed to target new blood vessel cells expressing VEGFR.In this research,a pcDNA3.1-IgG leader-VEGF-hFc eukaryotic expression vector was constructed and transfected into CHO/dhFr^- cells.Fusion proteins were secreted by CHO/dhFr^- cells,followed by affinity purification.Homo non-small-cell lung carcinoma SCID mouse tumor model was constructed with A549 cells.To study the ability of this fusion protein to suppress tumor growth,mouse veins were injected with 10μg fusion proteins.After 4 administrations, compared with the control group,the growth curve of tumor suggests that the tumor of experimental group mouse was suppressed,and in some cases even eliminated.These data showed that VEGF-hFc can suppress tumor growth up to 90%.更多还原