Purified DENV-2-induced <i>in vitro</i> mTRAIL expression and IFN-α production by purified plasmacytoid dendritic cells.

<p>PBMCs from healthy donors were stimulated overnight with DENV-2, mock or none (unstimulated). (<b>A</b>) mTRAIL expression profile on pDCs gated from PBMCs (overlay) and (<b>B</b>) mTRAIL positive pDCs for three donors induced by mock SNT (orange) or DENV-2 SNT (blue) using unstimulated (grey fill) pDCs as negative control. DENV positive C6/36 cells infected for 48 h with supernatant of DENV-2-infected C6/36 cells (DENV-2 SNT) or ultracentrifuged DENV-2 SNT (DENV-2 UC) as described in M&M and <a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0002257#pntd.0002257.s001" target="_blank">figure S1</a>. (<b>C</b>) DENV antigens/AlexaFluor488 (green) and nucleus/DAPI (blue) of C6/36 cells infected with DENV-2 SNT (left) and UC (right) at the same inocula dilution (10⁻³). (<b>D</b>) DENV positive C6/36 cells by flow cytometry in which cells were infected with SNT (orange) or UC (blue) DENV-2 inocula at different dilutions. PBMCs from healthy donors were stimulated overnight with DENV-2 UC, mock UC or none (unstimulated). (<b>E</b>) mTRAIL expression profile on pDCs gated from PBMCs (overlay) and (<b>F</b>) mTRAIL positive pDCs for four donors induced by mock UC (orange) or DENV-2 UC (blue) using unstimulated (grey fill) pDCs as negative control. Freshly purified pDCs were stimulated overnight with DENV-2 UC, mock UC or not (unstimulated). (<b>G</b>) TRAIL expression induced by different MOIs of DENV-2 UC (blue) using unstimulated cells (grey) as negative control. (<b>H</b>) Purified pDCs positive for mTRAIL expression and (<b>I</b>) IFN-α secretion by unstimulated (grey), mock UC (orange), DENV-2-UC-stimulated pDCs pre-treated (black) or not (blue) with chloroquine, for four donors. Values were submitted to paired t test in which * p<0.05 and ** p<0.005.