A) Frequency of BST2+ pDC among PBMCs cultured overnight in presence or absence of TLR9L and pre-treated or not (2 hours before TLR9L stimulation) with IFN-γ, IL-4, IL-10 or TNF-α; medians and IQRs of experiments from N=6 independent donors are shown; * P<0.05. B) Change in TLR9L-stimulated BST2-PE MFI induced by pre-treatment with IFN-γ, IL-4, IL-10 or TNF-α in different subsets of PBMCs; all results were normalized against TLR9L-treated PBMCs with no cytokines, indicated by grey dashed line; medians and IQRs of experiments from N=6 independent donors are shown; * P<0.05 compared to TLR9L-treated PBMCs with no cytokines. C) IFN-α was measured by ELISA in supernatants from PBMCs cultured overnight in presence or absence of TLR9L and pre-treated or not (2 hours before TLR9L stimulation) with IFN-γ, IL-4, IL-10 or TNF-α; cells were pre-incubated (30 min before TLR9L stimulation) or not with the BST2-specific blocking Ab 26F8 or isotype control antibody; medians and IQRs of experiments from N=6 independent donors are shown; dark grey dashed line and light grey shaded area indicate median and IQR of TLR9L-stimulated PBMCs without cytoikine pre-treatment (first data set on the left); * P<0.05 compared to unstimulated control (no TLR9L) for each cytokine pre-treatment; § P<0.05 compared to TLR9L-stimulated with no cytokine pretreatment.