表达乙型肝炎病毒表面抗原基因又形成多角体的杆状病毒

用形成包含体(OCC~+)并能利用人工合成启动序列和多角体XIV启动子表达外源基因的转移载体质粒pSXIVVI~+X3,将乙型肝炎病毒表面抗原(HBsAg)基因和多角体基因同时插入无包含体的粉纹夜蛾核型多角体病毒TnNPV-SVI-G基因组中,得到表达HBsAg基因又形成包含体(多角体)的重组毒侏TnNPV-HBs85-OCC~+。与利用野生型多角体启动子表达HBsAg基因的无包含体毒株TnNPV-HBsD4不同,TnNPV-HBs85-OCC~+由于具包含体,能以口服方式大规模感染粉纹夜蛾(Trichoplusia ni)幼虫,且HBsAg基因在草地夜蛾(Spodoptera frugiperda)离体细胞中的表达量要比前者高约37％,在虫体中的表达则更高。

Expression of Hepatitis B Virus Surface Antigen Using a Baculovirus Vector with the Polyhedrin Gene

Using a polyhedrin-positive transfer plasmid and a nonoccluded (OCC-) parental recombinant, an occluded (OCC~+)recombinant baculovirusdesignated TnNPV-HBs85-OCC~+ was successfully constructed which contained the gene coding for the hepatitis B virus surface antigen under the dual control of the synthetic and XIV promoters, Infection of Tvichoplusia ni larvae with TnNPVHBs85-OCC~+ can be introduced as a contaminant of the diet rather than the conventional baculovirus OCC~- expression vector in which the recombinant viruses must be injected into the host hemocoel individually, The expression level of HBsAg gene under the control of the synthetic and XIV promoters in Spodoptera frugiperda cells has been increased by 40% compared with that of the wild-type polyhedrin promoter alone, When T.ni larvae are used the expression level of HBsAg gene may increase to four to five folds of that by the wild-type polyhedrin promoter,