Tumor-specific cytotoxicity induced by combination therapy with WPRE-enhanced DNA vaccine and boosts with ch14.18–IL-2 fusion protein.
Cytotoxicity was induced by mouse splenocytes isolated 2 days after final boost with ch14.18–IL-2 and cocultured for specific expansion with irradiated NXS2 tumor cells for 2 days. Specific lysis was assessed at various T/E ratios in a standard 4-hour 51Cr release assay for splenocytes of mice immunized with either pcDNA3.1mTH (○); boosted with the ch14.18–IL-2 fusion protein in addition to mTH-vaccination (▴); WPRE-enhanced mTH vaccine, pcDNA3.1mTH-WPRE (▿); and a combination therapy of mTH-WPRE vaccination plus ch14.18–IL-2 fusion protein boost (▪). Results were compared with controls either immunized with the empty vector (●) or treated with the ch14.18–IL-2 fusion protein alone (■).
