Lymphoid progenitors are a source of IKDCs, and their formation is insensitive to Notch receptor ligation. LSKs and RAG-1⁺ ELPs were sorted from BM and placed in coculture with either vector (A) or Delta-like-1–transduced (B) OP9 stromal cells for 8 days in the presence of Flk-2/Flt-3 ligand. The indicated flow cytometry gates were used to discriminate B220⁺CD19⁻CD11c⁺Ly6C⁻ IKDCs, B220⁺CD19⁻CD11c⁺Ly6C⁺ pDCs, and B220⁻CD19⁻CD11c⁺ cDCs. Total numbers of recovered cells of each type were calculated and expressed in the graphs as yields per input progenitor (mean ± SEM). Asterisks denote significant differences (P < .05) by t test.