Figure 6.

Enforced IRF4 expression directs the development of the ERα/E2-dependent CD11b^int Ly6C⁻ DC subset in the absence of ERα signaling. Lin⁻ ERα^−/− BM cells were transduced with MiG-GFP (A-F) or MiG-IRF4-GFP (G-L). Transduced cells were incubated in GM-CSF for 5 days before assessment of DC subsets by flow cytometry. IRF4 expression was assessed in GFP⁻ (dotted line) and GFP⁺ (solid line) fractions in (A-B) MiG-GFP– or (G-H) MiG-IRF4-GFP– transduced cells. The MFI of anti-IRF4 binding to GFP⁺ and GFP⁻ cells is indicated in panels B and H. The shaded histogram indicates the binding of anti-IRF4 Ab precincubated with blocking peptide. In MiG-GFP–transduced cell cultures, CD11c⁺ DCs in the GFP⁻ (C) and GFP⁺ (E) cell fractions are primarily CD11b^hi Ly6C⁺ (panels D and F gated on CD11c⁺ cells shown in panels C and E). The percentage of cells with the bar or box gates is indicated. In MiG-IRF4-GFP–transduced cultures, CD11c⁺ DCs in the GFP⁻ cell fraction (I) are also primarily CD11b^hi Ly6C⁺ (J, gated on CD11c⁺ cells shown in panel I). In contrast, the percentage of CD11c⁺ DCs in the GFP⁺ fraction (K) is significantly increased, and the majority of DCs is CD11b^int Ly6C⁻ (L, gated on CD11c⁺ cells shown in panel K). Data are representative of 4 independent experiments.