Figure 3.

PU.1 Controls the Development of PU.1^hiFlt3⁺MHCII⁺ R2 Monocytes at Steady State

(A and B) Expression of PU.1 (black shading) and isotype control (gray shading) within Ly6C^hiCD115⁺ monocytes (R1 and R2) and pre-DCs (R3) (A) and in Ly6C^hiMHCII⁻, Ly6C⁺MHCII⁺, and Ly6C⁻MHCII⁺CD115⁺ cells (B) in the blood as seen by intra-nuclear staining of PU1 by flow cytometry. Numbers within plots indicate the MFI of PU.1.

(C–E) Representative flow cytometric analysis of the blood of Sfpi1^+/+ and Sfpi1^+/− mice at steady state. (C) Comparison of total (SIRPα⁺CD115⁺), Ly6C⁺, and Ly6C^lo blood monocytes by flow cytometry and quantification as the percentage of total live cells. (D and E) Comparison of Ly6C⁺MHCII⁻, Ly6C⁺MHCII⁺, and Ly6C⁻MHCII⁺ cells within SIRPα⁺CD115⁺ monocytes (D) and of R1–R3 within Ly6C^hi MHCII^+/− monocytes (E) in the BM and blood. Gray bars indicate intracellular staining for MHCII.

Data represent the mean ± SEM of three mice per group from three identical experiments (^∗p < 0.05,^∗∗p < 0.005, ^∗∗∗p < 0.0005; Student’s t test). Please also refer to Figure S3.