A construction strategy for a baculovirus-silkworm multigene expression system and its application for coexpression of type I and type II interferons

Liu, Xingjian; Yang, Xin; Mehboob, Arslan; Hu, Xiaoyuan; Yi, Yongzhu; Li, Yinü; Zhang, Zhifang

In the present study, the coexpression of type I and II IFNs at different gene sites was successfully achieved using a single recombinant baculovirus. The type I IFN chIFN-α gene was introduced at the polyhedron gene site. The chIFN-γ gene, a type II IFN-encoding gene, was inserted at the p10 gene site. The antiviral potential of the coexpression product was five to ten times higher than that of any single-expression product. After heat and acid treatment, the remaining IFN-α antiviral activity of the coexpression product was approximately two times greater than that of the chIFN-α single-expression product. This finding indicates that the expression level of IFN-α in the reBm-Cαγ product was significantly higher than that in the reBm-Cα product. ELISA results further augmented that multi-IFN expression in the coexpression product was higher than that in the single-expression product. This result was consistent with the antiviral assay. The increase in expression level is due to deletion of the p10 gene. Just like polyhedrin gene, p10 is a nonessential gene for baculovirus replication and budded virus production. And also, it is nonessential for recombinant protein expression, but with high expression level (Hitchman et al., 2010) .