BDCA-2⁺ pDCs that develop onto OP9-Del1 stromal cells have characteristic markers of pDCs. (A) Flow cytometric analysis on the cells produced in OP9-Del1 coculture, representative of 3 experiments. (B) Purified pDCs were obtained by flow cytometric isolation of CD45⁺ CD123⁺ BDCA-2⁺ cells from OP9-Del1 coculture. Cells were then spun on glass slides and stained with Wright Giemsa. Photograph was obtained with a Leica DFC320 digital color camera mounted onto a Leica DMRB microscope (Leica Microsystems, Wetzlar, Germany) using a 60×/1.32 NA oil objective and Leica IM 50 version 4.0 software. (C) Analysis of mRNA transcripts expressed by 1 × 10⁶ cells obtained at day 20 of culture of CD34⁺ cells onto OP9Del1 or OP9-C. (D) mRNA transcripts expressed by sorted BDCA-4⁺ CD123 ⁺ cells.