猪繁殖与呼吸综合征病毒GP5蛋白实验性核酸疫苗的构建及其免疫原性的初步研究

Study on Immunogenicity of DNA Vaccine Expressing Porcine Reproductive and Respiratory Syndrome Virus(PRRSV) ORF5 Gene

扩增了猪繁殖与呼吸综合征病毒(PRRSV)长春分离株ORF5基因,并将其克隆至真核表达载体pVAX1、pVIR-IL-18的CMV启动子下游,构建成真核表达质粒。通过Western blot以及IFA检测方法确认,所构建的2个重组DNA疫苗质粒在真核细胞能进行有效的转录,并表达了目的蛋白(GP5)。同时辅以不同佐剂进行了BALB/c小鼠免疫试验,检测了免疫后的ELISA抗体水平和脾T淋巴细胞亚群数量。结果表明:共表达猪IL-18基因的核酸疫苗pVIR-IL-18-ORF5免疫后的ELISA抗体水平和脾T淋巴细胞亚群数量均优于pVAX1-ORF5,而且加佐剂实验组优于未加佐剂的实验组。

In this study,ORF5 gene of the Changchun PRRSV strain was amplified and cloned into pVAX1 and pVIR-IL-18 eukaryotic expressing vectors. The two recombinant DNA vaccines were transcribed and expressed in eukaryotic cells effectively through Western blot and IFA identification. At the same time, the two DNA vaccines were used to immunize BALB/c mice added with different immunoadjuvants. The ELISA antibody and the number of spleen T lymphocyte subgroups were tested after immunization. The result was that the ELISA antibody and the number of spleen T lymphocyte subgroups induced by DNA vaccine pVIR-IL-18-ORF5 were higher than those induced by pVAX1- ORF5 and those of adjuvant immunized group were better than those of no adjuvant immunized group regardless of humoral or cellular immune level.