Sequential treatment with mAb 440c and saporin depletes IPCs in vitro. (A) Expression of 440c on bone marrow cells cultured in FLT3-L for 10 days. CD11c^- cells were excluded from the gate. 440c is highly expressed on B220⁺ cells, which represent fully developed IPCs. (B-C) Depletion of CD11c⁺/B220⁺ cells from FLT3-L-derived bone marrow IPCs by treatment with 440c-saporin. Cells were stained on ice with biotinylated-440c (B) or a biotinylated control antibody (C), followed by avidin-saporin, cultured for an additional 36 hours, and analyzed for residual presence of CD11c⁺/B220⁺ cells. The percentage of gated cells is indicated. Results are representative of 3 separate experiments.