【摘要】 本研究设计了CP1和CP10两种嵌合肽免疫原,它们由人绒毛膜促性腺激素β亚单位(β- hCG)3个线性B细胞表位(BCE)以及包括来自乙肝表面抗原和破伤风类毒素2个广谱性T细胞表位(TCE)的6个TCEs组合而成。编码CP1及其衍生物CP10的人工基因分别重组插入热诱导pBV221载体后,均能在大肠杆菌中以约占细菌总蛋白1％的比例被表达。在蛋白印迹试验中,在SDS-聚丙烯酰胺凝胶电泳凝胶上显示约为16．5 kD分子量的CP1和CP10表达蛋白,能被抗各插入表位单克隆或多克隆抗体识别。各表达蛋白可用制备性PAGE方法一步纯化,纯化产物均显示95％以上的电泳均一性,纯化得率可达到每升培养液1-2mg水平。以它们为抗原主动免疫小鼠,都能分别产生识别CP1或CP10和天然β-hCG的抗血清,并都能在它们的抗血清中检测到各插入抗原表位的抗体。hCG CPs的可获得性及其能诱导各表位抗体生成特征,有可能成为研制hCG抗生育和肿瘤治疗性疫苗的新的候选免疫原。更多还原

【Abstract】 Two bio-synthesizing chimeric peptide (CP) immunogens named CP1 and CP10 have been designed,which consist of three linear B cell epitopes (BCE) of human chorionic go-nadotropinβsubunit (β-hCG) and six foreign T cell epitopes including two "promiscuous" TCEs from hepatitis B surface antigen and tetanus toxoid. Two artificial genes encoding CP1 and its derivative CP10 were synthesized, which could be expressed in E.coli at the level of about 1% of the total cell proteins when inserted into the thermo-induction vector respectively. In Western blot tests,the expressed CP1 and CP10 proteins with about 16.5 kD shown on the SDS-polyacrylamide gel electrophoresis (PAGE) gel can be recognized by the monoclonal or polyclonal antibodies specific to each linear epitope ofβ-hCG. Each of expressed proteins can be purified with 95% relative homogeneity using our improved method of preparative gel PAGE. Their yields were about 1-2 mg per 1 L culture. Also,the CP1 and CP10 immunogens can induce antibodies in mice that recognize recombinant CP1 or CP10 and naturalβ-hCG,and there are three anti-β5,β9 andβ8 BCE antibodies in their antisera. The construction and expression ofβ-hCG CP1 and CP10 will provide new immunogens for developing an ideal and superior hCG birth control and/or tumor therapeutic vaccine.更多还原