基于乙肝核心抗原和猪流行性腹泻病毒S蛋白B细胞复合表位基因重组疫苗的免疫原性研究

为了研制新型、有效的猪流行性腹泻病毒(PEDV)疫苗,本研究以乙肝核心抗原蛋白(HBcAg)作为多表位免疫原的载体蛋白,将PEDV S蛋白中的3个B细胞表位基因与S1截短序列基因串联后,插入到编码HBcAg的免疫显性区的基因中,构建重组质粒HBcAg-PE,并转化至大肠杆菌BL21(DE3)中进行表达。重组蛋白HBPE经过纯化和Western-blot鉴定后,以不同剂量的重组蛋白通过肌肉注射途径免疫BALB/c小鼠,对其免疫效果进行了初步评价。结果显示,重组蛋白HBPE在BL21(DE3)中以沉淀形式表达,纯化、复性后的重组蛋白HBPE能够与PEDV阳性血清发生特异性反应。重组蛋白HBPE能够刺激小鼠产生抗PEDV特异性抗体,同时可以产生相关的Th1型和Th2型细胞因子。上述结果表明,本研究成功构建了PEDV重组B细胞复合表位抗原HBPE,并在小鼠模型中初步评价了其免疫原性,为今后新型PEDV基因工程疫苗的研制提供了新的思路。

Immunogenicity of gentic vaccine based on recombinant hepatitis B core antigen and B cell multi-epitopes of porcine epidemic diarrhea virus spike glycoprotein

In present study,in order to develop a new and effective porcine epidemic diarrhea virus(PEDV)vaccine,three B cell epitopes and the truncated S1 gene of PEDV spike protein were combined and inserted into the immunodominant region of the HBc Ag.Then the constructed recombinant plasmid HBc Ag-PE was transformed to E.coli BL21(DE3)for expression.After purification and identification by Western-blot,the expressed recombinant proteins HBPE were injected into BALB/c mice as vaccine antigen with different doses through intramuscular injection and its immune effect were preliminary evaluated.The results showed that the recombinant proteins HBPE was expressed as precipitation form and it could reacted specifically with PEDV-positive serum after purification and renaturation.Besides,the HBPE could induce anti-PEDV specific antibodies and the related Th1 and Th2 cytokines in mice.The above results indicate that the recombinant compound epitope antigen of PEDV was successfully constructed,and its immunogenicity as a new vaccine candidate was evaluated in the mice in this study.The results of this study provided a new idea for the development of PEDV genetic engineering vaccine in the future.