Dose-responsive activation of peripheral blood pDCs and B-cells by CpG. These are dose-response histograms showing activation of pDCs and B cells (measured by expression of CD83) with incremental amounts of CpG. In this study, leukocytes were isolated from heparinized peripheral blood from patients or healthy controls by Ficoll gradient and cultured in complete media at 37°C, 5% CO₂ for 18 hours with 0, 3, or 10 μg/mL CpG ODN PF-3512676. Afterward, cells were washed and stained with the following antibody panel: CD3, CD14, CD16, CD56 (lin)–FITC, CD83-PE, CD123-PE-Cy7, HLA-DR-allophycocyanin, and CD19-AMCyan. Then, the sensitivity was assessed on an LSR-II flow cytometer. The responsiveness of TLR9 to CpG was similar in MF compared with healthy controls in both pDCs and B cells.