传染性法氏囊病病毒多聚蛋白基因在家蚕中的表达

将传染性法氏囊病病毒(IBDV)细胞致弱株(JD1株)的基因组A节段基因重组于家蚕杆状病毒转移载体pAcHLT-C中，获得的重组转移载体pAcHLT-C-A与线性化病毒Bm-BacPAK6 DNA共转染家蚕培养细胞，获得重组病毒BacPAK-A。DIG标记的DNA点杂交证实重组病毒基因组中含有A节段基因，重组病毒感染家蚕5龄幼虫进行表达， ELISA和Western blotting等结果表明多聚蛋白基因在蚕体内得到了表达，表达产物具有免疫反应性，表达量在感染后5～6 d达到最高。家蚕生物反应器表达IBDV多聚蛋白具有我国的资源优势，为今后研制低成本、实用化的IBDV基因工程疫苗打下基础。

Expression of Polyprotein of Infectious Bursal Disease Virus in Bombyx mori

Segment A of the genome of infectious bursal disease virus(IBDV) encodes structure protein VP2 and VP3 and protease VP4. In this study a polyprotein gene of IBDV was inserted into a Bombyx mori baculovirus transfer vector pAcHLT-C and cotransfected into BmN cells with linear genome DNA of virus Bm-BacPAK6. Dot hybridization suggested that the segment A of the virus genome was inserted in the genome of Bm-BacPAK6. The silkworm of fifth instars were infected by the recombinant virus and the immunogenicity of the infected larvae's blood were examined with ELISA, SDS-PAGE and Western blotting. It appears that the recombinant polyprotein has the property of immunoreactivity and the expression in larvae reached the pick 5-day post infection.