Suppression of Bm-Caspase-1 Expression in BmN Cells Enhances Recombinant Protein Production in a Baculovirus Expression Vector System

Baculovirus expression vector systems (BEVSs) have been widely used for recombinant protein production. Many studies have tried to improve the recombinant protein production by either modification of BEVSs vectors or by cell line selection. In this study, using a modified shRNA vector, we established a stable Bombyx mori cell line that significantly inhibits expression of caspase-1 after selection. We further compared cell proliferation and viability between caspase-1-suppressed cells and control cells, and found that there is no significant difference in these stable cell lines. We utilized these cell lines to analyze recombinant protein production after infection with recombinant baculovirus. We found that both intracellular and extracellular recombinant protein production significantly increased when expression of caspase-1 is inhibited in BmN cells. These data indicate that blocking the apoptotic pathway is a promising way to enhance recombinant protein production in BEVSs.