草鱼出血病基因疫苗的免疫效果

The research about protective efficiency of DNA vaccine against hemorrhage disease of grass carp

为探讨含有草鱼呼肠孤病毒外衣壳蛋白VP6基因的重组基因疫苗对草鱼出血病的免疫效果,将重组基因疫苗分别配制为10、30和60μg三个梯度,同时设30μg pFastBacTMDual空载体组,均以等体积的氢氧化铝佐剂为免疫增强剂,对草鱼进行注射,以未经处理的草鱼作为对照组。定期采血测定抗体效价,最后对各组草鱼进行攻毒试验并计算死亡率和免疫保护力。结果显示:注射疫苗的三组草鱼均产生抗体,10μg组效价为1∶6～1∶11;30μg组为1∶9～1∶13;60μg组为1∶11～1∶17,且各组效价均在第28天测定最高,免疫保护率依次为100%、100%和95%,而空载体组和对照组为70%和0%。研究表明,疫苗能够诱导草鱼产生免疫反应,为草鱼出血病核酸疫苗的生产应用和产业化提供了重要的理论依据。

The aim of present study was to explore the immune efficacy of DNA vaccines which were prepared from recombinant grass carp reovirus（GCRV） outer capsid protein VP6. The experimental grass carps were divided into three groups and injected based on doses of recombinant plasmids as follows： 10 μg per fish,30 μg per fish, 60 μg per fish and 30 μg pFastBacTMDualr per fish. Every group was mixed with equal volumes of aluminum hydroxide adjuvant except control（normal fish）. Antibody titers were detected regularly after injection, and mortality rates and immunoprotective effect were calculated after challenge experiment. The results showed that antibodies were generated. The antibody titer of 10 μg group was 1：6-1：11,30μg group was1：9-1：13,and 60 μg group was 1：11-1：17, and the highest titer appeared on 28th day,the protective rate was 100%, 100% and 95% respectively,in contrast,pFastBacTMDual group and control was just 70% and 0%. All results suggested that the vaccines constructed had preferred protection efficiency. Therefore,the studies provided important academic foundation for the development and application of the GCRV DNA vaccine.