Ad.DCs and mDCs activate NK cells via tmTNF and trans-IL-15. Ad.DCs (A) and mDCs (B) were cocultured with NK cells for 24 hours in the presence of 20 μg/mL of human and mouse nonreactive IgG, anti-TNF antibody (αTNF), TNFR2-Fc construct (EN), anti–IL-15 antibody (αIL-15), both αTNF and αIL-15 (αTNF + αIL-15), or DN-TNF. NK-cell activation was tested by IFN-γ ELISPOT. Data are representative of 3 experiments and are mean ± SEM of triplicates. *P < .05.