Figure 3.
pDC-derived IFNα inhibits IL-8 production in monocytes and cDCs. (A) PBMCs were stimulated for 5 h with FLU ± anti-IFNAR2. ICCS and surface staining were performed to evaluate IL-8 production in stimulated pDCs. The plots show IL-8 levels in BDCA-2+ BDCA-4+ cells. (B) Purified pDCs were stimulated for 20 h with 50 HAU/ml FLU ± anti-IFNAR2, and supernatants were harvested and analyzed by Luminex. Data shown are the mean of results obtained from two donors. (C) PBMCs were stimulated for 5 h with 50 HAU/ml FLU ± anti-IFNAR2. ICCS and surface staining were performed to evaluate IL-8 production in monocytes (gated on CD14+ expression), cDCs (identified as BDCA-1+ CD19− cells), and B cells (gated on CD19+ expression). For each dataset, results are representative of two independent experiments. (D) 5 × 105 PBMCs were incubated for 5 h with 50 μg/ml CpG-2216 ± anti-IFNAR2. Supernatants were harvested, and IL-8 levels were evaluated by Luminex. (E) 106 PBMCs were cultured in the presence of 1 ng/ml rTNFα (solid line) or media alone (dashed line) in the presence of the increasing amounts of rIFNα. After 20 h, supernatants were harvested and IL-8 levels were evaluated by Luminex. Data show the average values obtained from experiments performed on two healthy donors. (F) A schematic representation illustrating the opposing effects of pDC-derived TNFα and IFNα on IL-8 production.