一种新型人源化鲑鱼降钙素突变体的构建与表达  

Construction and Expression of a New Humanized Salmon Calcitonin Variant

作　　者：刘深基[1] 陈松森[1] 狄旭[1] 熊安琪[1] 张友鸿[1] 

机构地区：[1]中国医学科学院 中国协和医科大学 基础医学研究所生物化学与分子生物学研究室,北京100005

出　　处：《中国医学科学院学报》2001年第4期351-355,共5页Acta Academiae Medicinae Sinicae

摘　　要：目的 降低鲑鱼降钙素（sCT）对人体的免疫原性。方法 设计并合成人源化鲑鱼降钙素（11 ～ 17）hsCT基因，用基因重组方法构建表达载体，转入大肠杆菌G1724中，经色氨酸诱导表达；用渗透压法处理菌体纯化融合蛋白；以大鼠血清钙浓度降低方法测定hsCT生物活性；用定量Western blot法测定hsCT免疫原性。结果 重组pTrxFus-hsCT质粒在大肠杆菌中获得高效可溶性融合蛋白表达, 表达水平达46%以上, 并得到纯度约90%的融合蛋白,rhsCT保存了鲑鱼降钙素前体活性的一半以上, 免疫原性降低了55%。结论 获得一种新型人源化降钙素（11 ～ 17）hsCT，其保存较高sCT前体的活性，免疫原性明显降低。Objective To study the reduction of immunogenicity of salmon calcitonin(sCT)． Methods A new(11 ～ 17)humanized salmon calcitonin variant gene(11 ～ 17)hsCT was designed and synthesized to construct recombinant expression vector and express in E．coli G1724 with tryptophan． The fusion protein of humanized salmon calcitonin and thioredoxin(Trx-hsCT)obtained from the bacterial by means of osmotic pressure； The bioactivity of Trx-hsCT was estimated by serum calcium reduction me- thod in rat； The quantitative Western blot analysis was used for detecting the immunogenicity of hsCT． Results Recombinant expressing vector pTrxFus-hsCT was expressed in high level and soluble in E．coli G1724, reaching 46% of total bacterial protein and obtaining the fusion protein of 90% pur- ity； Special bioactivity of hsCT was preserved that of half pre-sCT and its immunogenicity reduced ov- er 50% that of pre-sCT． Conclusion Obtain a new humanized salmon calcitonin variant(11 ～ 17) hsCT which maintains a rather high bioactivity over pre-sCT and decreases distinctly its immunogenicity．

关 键 词：人源化降钙素 重组 免疫原性 生物活性 

分 类 号：R977.5[医药卫生—药品]