Figure 1. Conditional deletion of IRF8 does not impair myelopoiesis.

(A) Flow cytometry plots of cell surface CD11b and F4/80 expression by M-CSF–generated BM-derived macrophages (BMDMs) from C57BL/6-derived WT or IRF8-cKO mice. (B) Intracellular flow cytometric analysis of IRF8 expression by BMDMs from A, incubated with vehicle or IFN-γ (100 U/ml) or IL-4 (20ng/ml) for 24 hours. Data shown as mean fluorescence intensity (MFI) (n = 3 biologic replicates). (C) Flow cytometry plots of CD11c⁺F4/80⁺ macrophages from a bronchial alveolar lavage (BAL) of WT or IRF8-cKO mice, as in A. (D) Intracellular flow cytometric analysis of IRF8 expression by BAL-derived macrophages from C, incubated with vehicle or IFN-γ (100 U/ml) for 24 hours. Data shown as MFI (n = 5–6 biologic replicates). (E) iNOS or Arg1 mRNA levels by BMDMs from A incubated with vehicle or IFN-γ (100 U/ml) or IL-4 (1 ng/ml) for 24 hours. (F) Percentages of monocytes in peripheral blood from WT (IRF8^fl/fl) or IRF8-cKO mice. (G) Percentages of CD11b⁺F4/80⁺ macrophages in spleens from WT (IRF8^fl/fl) or IRF8-cKO mice. (H) Percentages of the indicated progenitors of WT or IRF8-cKO mice. n = 6 mice for each group pooled from 2 separate experiments for panels F–H. No significant differences were observed between WT and IRF8-cKO mice for all parameters examined in H. Data represent mean ± SEM, and statistical significance was determined by a 2-tailed Mann-Whitney U test. *P < 0.05.