Effect of posttranscriptional modification of a DNA vaccine with WPRE combined with boosts of ch14.18–IL-2 fusion protein on IFN-γ expression in CD8⁺ T cells.

Splenocytes from A/J mice, recovered 2 days after final boost with ch14.18–IL-2, were cocultured with irradiated NXS2 tumor cells for antigen-specific proliferation and activated polyclonally as described in “Materials and methods.” IFN-γ expression in CD8⁺ T cells was determined by intracellular staining. Differences in IFN-γ expression of CD8⁺ T cells between mice treated with a combination of mTH or mTH-WPRE immunization and ch14.18–IL-2 boosts and all other groups were statistically significant (P ≤ .004). Data are expressed as means ± SE from 2 different experiments.