Trans-complementation of polyhedrin by a stably transformed Sf9 insect cell line allows occ− baculovirus occlusion and larval per os infectivity

Transfection of Sf9 cells with plasmid carrying polyhedrin gene and stable cell lines established by selection with blasticidin showed polyhedrin expression and, moreover, crystalline polyhedron-like structures were visualized by optic microscopy. Oral infectivity was demonstrated by fluorescence detection in Rachiplusia nu larvae infected with occluded AcGFPpolh− baculovirus obtained using the system presented here.