CDPs give rise to CCR9⁻ pDC-like precursors. (A) CD45.2⁺ CDPs were cultured for 4 days with total CD45.1⁺ BM cells in medium supplemented with Flt3L and analyzed for the expression of Siglec-H, CD11c, BST2, CCR9, and MHCII by flow cytometry (representative results of 4 replicates are shown). (B) CD45.2⁺ CDPs were transferred intravenously into CD45.1⁺ mice and the expression of Siglec-H, CD11c, BST2, and CCR9 on PI⁻ CD45.2⁺ progeny was analyzed after 5 days in BM and spleen by flow cytometry (results of one representative of 3 transfers are shown). (C) CD45.2⁺ CDPs were transferred IV into CD45.1⁺ mice and the expression of BST2 and CCR9 on PI⁻CD45.2⁺Siglec-H⁺ progeny was analyzed 7 days later in BM and spleen by flow cytometry (results of one representative of 6 transfers are shown).