IL-12 and IFN-α contribute to NK-cell activation induced by HCMV-infected moDCs. Freshly purified NK cells were cultured with target cells for 24 hours as described in Figure 2A-B (moDCs/NK = 1:4; TB40/E moDCs: 80% IE-1/IE-2⁺ cells). In parallel, the effect of IL-12-specific, IFNAR-specific, and control (myc) mAbs was tested. (A) IFN-γ production was measured by ELISA (mean ± SD of triplicates). (B) CD69 expression on NK cells was assessed by flow cytometry. NK cells purified by negative selection from PBMCs stimulated overnight with IL-2 were cocultured for 5 hours with target cells as described in “NK-cell functional assays.” In parallel, the effect of IL-12-specific, IFNAR-specific, and control (myc) mAbs was tested. Surface CD107a expression in CD56⁺ cells was analyzed by flow cytometry. (C) The percentage of CD56⁺CD107a⁺ is included in each dot plot. Results of a representative experiment of 3 performed are shown.