杀伤血管内皮生长因子受体1阳性细胞的靶向毒素  

A Fusion Protein Targeting The Vascular Endothelial Growth Factor Receptor Ⅰ(VEGFR-1)

作　　者：白向阳[1] 倪剑锋[1] 吕安国[1] 吴文芳[1] 牛瑞芳[2] 

机构地区：[1]中国科学院沈阳应用生态研究所 [2]天津医科大学肿瘤医院,天津300060

出　　处：《生物化学与生物物理进展》2005年第4期365-370,共6页Progress In Biochemistry and Biophysics

摘　　要：白喉毒素(diphtheria toxin DT) 是棒状白喉杆菌被茁噬菌体感染后分泌的一种外毒素. 它可以阻断真核细胞的蛋白质合成,杀死细胞. 血管内皮生长因子(VEGF) 的R82A,K84A,H86A突变体可以和肿瘤血管上高表达的VEGF受体1 (VEGFR-1) 特异性结合. 首先从白喉杆菌中提取基因组DNA,扩增出白喉毒素C区、T区基因. 并运用点突变技术,制成VEGF的R82A,K84A,H86A突变体. 利用这个可以和肿瘤血管上特异性受体相结合的VEGF的突变体,代替白喉毒素上的受体结合区,制成了针对VEGFR-1的靶向融合毒素——DT391-mVEGF. 以去除了受体结合区的DT391为阴性对照,细胞实验表明,融合毒素对VEGFR-1阳性的肿瘤细胞有特异性杀伤作用.Diphtheria toxin is an exotoxin secreted by Corynebacterium diphtheriae that has been lysogenized by P bacteriophage that carries the DT gene. It blocks protein synthesis and kills the target eukaryotic cell. The R82A, K84A, H86A mutant of vascular endothelial growth factor (VEGF) specially binds its receptor 1 (VEGFR-1) that is expressed highly on surface of tumor blood vessel. DT genomic DNA was extracted first and then the gene that coding the T domain and C domain of DT (DT391) were amplified. The R82A, K84A, H86A mutant were introduced to VEGF by site-directed mutagenesis. Then a VEGFR-I targeting fusion protein, DT391-mVEGF, was constructed by substituting the receptor binding domain of DT with the VEGF mutant which shows high affinity to a receptor expressed on tumor vascular. With DT391, a protein without the mVEGF domain of DT391-mVEGF, as a negative control in cytotoxicity assay, the hybrid protein DT391-mVEGF showed an inhibition to the growth of VEGFR-1 positive tumor cell.

关 键 词：白喉毒素 血管内皮生长因子(VEGF) 血管内皮生长因子受体1(VEGFR-1) 融合蛋白 

分 类 号：Q78[生物学—分子生物学]