小鹅瘟病毒“自杀性”DNA疫苗对小鼠免疫原性分析

Immunogenic analysis on suicidal DNA vaccine against gosling plague virus in mice

先将小鹅瘟病毒VP3基因克隆至"自杀性"DNA疫苗载体pSCA1构建pSCA-VP3重组质粒,对其鉴定后转染BHK-21细胞,通过间接免疫荧光检测VP3蛋白在体外的表达。将30只6周龄BALB/c小鼠随机分为3组,每组小鼠分别腿部肌肉注射100μg pSCA-VP3质粒,pSCA1空载体质粒和100μL PBS。以2周为间隔,共免疫3次。通过间接ELISA检测VP3蛋白特异性抗体水平,淋巴细胞增殖检测细胞免疫水平。结果表明:成功构建了"自杀性"DNA疫苗重组质粒pSCA-VP3;间接免疫荧光表明VP3蛋白在体外能够正常表达,且表达的蛋白具有良好的反应原性;相比于空载体组及阴性对照组,pSCA-VP3组小鼠产生了显著的体液免疫和细胞免疫反应。该研究为GPV的疫苗研制提供新的思路,为进一步临床应用研究提供科学依据。

The VP3 gene of GPV was amplified by PCR and then cloned to the suicidal DNA vector pSCA1.The resulting recombinant plasmids were identified and named pSCA-VP3.Then the recombinant plasmid was transfected into BHK-21 cells to detect VP3 protein expression in vitro.Thirty 6-week old BALB/c female mice were divided randomly into three groups（10mice per group）.The three groups of mice were injected with 100μg pSCA-VP3 plasmid,pSCA1empty plasmid and 100μL PBS,respectively.The plasmids were then injected intramuscularly into mice two times at2-week intervals individually.The empty plasmid pSCA1 and PBS was used as negative control.To evaluate the immunogenicity of the recombinant plasmids,specific antibodies against GPV were measured using an indirect enzymelinked immunosorbent assay.Cell-mediated immune responses were also examined using a lymphocyte proliferation assay.The results showed that the suicidal DNA vaccine was successfully constructed.The constructed plasmid could express VP3 protein in vitro.Moreover,the expressed protein had good reactionogenicity.Compared with the pSCA1 empty vector and PBS negative control groups,specific antibodies and lymphocyte proliferation responses were all induced significantly in mice immunized with pSCA-VP3.Our studies provided a new thread in GPV vaccine development,and some evidences for the further clinical utilization.