鸡传染性法氏囊病病毒VP2蛋白在昆虫细胞-杆状病毒表达系统中的分泌表达及免疫原性分析

Secreted Expression and Immunogenicity Analysis of VP2 Protein of Infectious Bursal Disease Virus in Baculovirus Expression System

根据杆状病毒表达系统的密码子偏好性,对鸡传染性法氏囊病毒(IBDV)VP 2基因序列进行密码子优化,然后合成序列。优化后的序列被定向克隆至转移载体pFast Bac^(TM)1,转化DH10Bac^(TM)感受态细胞获取重组杆状病毒穿梭质粒,转染昆虫细胞SF9,获得P0代重组杆状病毒。间接免疫荧光鉴定和Western blot分析结果显示,病毒reBac-VP2感染昆虫细胞后,能够在昆虫细胞的上清中稳定表达VP2蛋白,而且能够与IBDV的抗体发生特异性结合,具有良好的免疫原性。本试验成功构建了能够分泌表达VP2蛋白的重组杆状病毒,为IBDV诊断试剂及亚单位疫苗研发提供了工具。

The VP 2 nucleotide sequence of Infectious bursal disease virus(IBDV)was downloaded from NCBI GenBank database.The codon sequence was optimized based on the amino-acid composition bias of baculovirus-insect cell system.The optimized gene sequence was synthesized and cloned into pFast Bac^(TM)1,then transformed into DH10Bac^(TM) E.coli to obtain the baculovirus shuttle vectors.The recombinant bacmid DNA was extracted and transfected into insect cell SF9 according to the manual.Indirect immunofluorescence identification and Western blot analysis showed that after the virus reBac-VP2 infects insect cells,it can stably express VP2 protein in the supernatant of insect cells,and it can specifically bind to the antibody of chicken IBDV.This showed that the VP2 protein expressed in this study has good immunogenicity.It could be applied for further development of specific diagnostic method or investigation of IBDV pathogenesis.