Ectopic miR-146a expression affects pDC activation and maturation. (A) QPCR analysis of IL-6 and IFN-β mRNA levels in CAL-1 cells transduced with hTR control or with miR-146a cultured in medium or activated with TLR7 ligand R848 (10 μg/mL) for 4 hours. Shown are mean values ± SD of 2 independent experiments. The values for hTR-transduced cells cultured in medium are set to 1. *P < .05. (B) Flow cytometric analysis of CAL-1 cells after transduction with hTR control (gray line) or miR-146a (black line). Cells were activated overnight with the TLR7 ligand R848 and stained for expression of CD40, CD80, CD86, HLA-DR, and CCR7. The filled gray histograms represent isotype control antibody-stained cells. RCN, relative cell number. (C) Cells were analyzed as in panel B. Statistical analysis of the relative MFIs ± SD of 4 to 6 different experiments. MFIs of proteins expressed on hTR control cells are set to 1. *P < .05; **P < .01. (D) Primary pDCs isolated from blood were transfected with FITC-conjugated LNA-miR146a or LNA-control followed by activation with CpG-A (10 μg/mL) or medium only for 18 hours. Cells were analyzed by flow cytometry after staining with an anti–IFN-α antibody or isotype control antibody. Shown are the mean percentages ± SD of IFN-α–expressing pDCs of 2 independent experiments.