FIG. 6.

MVA induces earlier caspase activation in DCs than VV. (A) Immature DCs were mock treated, infected with rMVA-GFP or rVV-EGFP at an MOI of 1 or 10, or UV treated. Apoptosis was measured at 3, 11, 23, and 45 h by one-step cellular caspase 3/7 assay. (B) The same experiment was performed as in panel A, with the addition of the pan-caspase inhibitor Z-VAD-FMK to demonstrate the specificity of the assay. (C) Immature DCs were either mock infected (dashed line, triangles) or were infected with rVV-EGFP (solid line, squares) or rMVA-GFP (solid line, circles) at an MOI of 10. Apoptosis was measured at 0, 14, 23, and 48 h postinfection by flow cytometry after staining of the cells with the fluorogenic caspase substrate R2D2. These data are representative of results from four independent experiments.