Influence of ATP on the ability of MoDCs to induce IFN-γ by naive and memory T cells. (A) Human naive and memory CD4⁺ T cells were cultured with CD3/CD28 T-cell expander beads in the presence of MoDC supernatants (stimulated with E coli in the presence or absence of ATP). IFN-γ was measured by ELISA. (B) As indicated, isotype (IgG1), anti–IL-12p70, or anti–IL-12/23p40 mAbs were added to the T-cell cultures. Data represent mean ± SEM of 6 experiments (using supernatants of 3 DC donors).