MURINE INTERLEUKIN-4 PRODUCTION WITH BACULOVIRUS - AN EASY AND RAPID METHOD FOR A SMALL-SCALE PRODUCTION OF FUNCTIONAL INTERLEUKINS

We described a baculovirus expression system for high level production of secreted murine recombinant IL-4. We have constructed a recombinan t baculovirus based on Autographa californica polyhedrosis virus, cont aining both a synthetic PCR-derived murine IL-4 cDNA under the control of the polyhedrin promoter and the lacZ gene under the control of the P10 promoter to allow an easy detection of recombinant virus. The bac ulovirus IL-4 was fully functional in biological assay and was present under two glycosylated forms in the supernatants of infected Sf9 cell s. We also detected a third unglycosylated intracytoplasmic form resul ting from a fusion between the 35 first amino acids of polyhedrin and the murine IL-4. Finally, confocal microscopy showed that this recombi nant protein was secreted along a classical pathway like in mammalian cells.