Spleen autofluorescent cells are macrophages and represent the red pulp macrophages of the spleen. Flow cytometry stainings on monocytes in the spleen, blood monocytes, spleen autofluorescent cells, M-CSF, and GM-CSF cultured monocyte-derived macrophages. (A-C, top) Representative histogram on spleen autofluorescent cells (blue line, specific staining; red shading, isotype control). (A-C, bottom) Summary of Δ MFIs of multiple stainings. (A) Intracellular staining for CD68. (B) CD163 staining. (C) CD169 staining. (D) Sorting strategy for splenocytes sorted into autofluorescent CD163^highCD14^low red pulp macrophages and nonautofluorescent CD163^intCD14^high spleen monocytes, and May-Grünwald-Giemsa stainings (original magnification ×40) of the sorted cell populations, representative of n = 8 experiments. Mean ± SEM of n ≥ 7 are shown for each group.