Distinct transcriptional profile of phagocytic macrophages. (A) Experimental strategy for transcriptomic analysis of phagocytic versus nonphagocytic macrophages. (B) Principal component analysis comparing the transcriptional profile of phagocytic and nonphagocytic macrophages from the bone marrow, spleen, and large intestine. Samples of phagocytic and nonphagocytic macrophages from the same pool of mice are linked by dashed lines. (C) Distance tree illustrating the relative transcriptional proximity of macrophages based on their tissue of residence and phagocytic capacity. For reference, the relative position of in vitro–polarized M0 (M-CSF), M1 (LPS + IFN-γ), and M2 (IL-4 + IL-13) macrophages (obtained from Li et al. [2015]) is shown. (D) K-means clustering (K = 9) of 634 differentially expressed genes in phagocytic (Pha) and nonphagocytic (Non) macrophages; n = 3 samples per group. (E) Validation by quantitative PCR of genes identified in the transcriptomic analyses of phagocytic and nonphagocytic from bone marrow, spleen, and large intestine; n = 5–6 samples per group from two independent experiments. All bars show mean ± SEM. *, P < 0.05; **, P < 0.01, as determined by paired Student’s t test analysis.