High-level expression of canine parvovirus VP2 using Bombyx mori nucleopolyhedrovirus vector

For the potential use as recombinant vaccine, canine parvovirus (CPV) major capsid protein VP2 was expressed using Bombyx mori nucleopolyhedrovirus (B mNPV) vector. CPV VP2 gene was introduced into polyhedrin-based BmNPV trans fer vector pBmKSK3, and recombinant virus BmK1-Parvo was pre pared. When an ti-CPV.VP2 monoclonal antibody was employed in immunofluorescence staining, an intense signal was observed within BmK1-Parvo-infected Bm5 cells but no t within uninfected cells or cells infected with a wild-type BmNPV-K1. In h emagglutination assay, the expression level of VP2 were 3.2 x 10(3) HA unit s/ml from infected Bm5 cells, 2.1 x 10(5) HA units/larvae from infected lar val fat body, and 1.6 x 10(6) HA units/ml from infected larval hemolymph. T hese results suggested that BmNPV vector system using B. mori larva as host could be applied to efficient mass-production of recombinant vaccines.