Monocyte, DC, and macrophage phenotypic and microarray analysis. (A) Monocytes and in vitro cultured DCs and macrophages were stained for surface expression of the indicated molecules and analyzed by flow cytometry (dotted lines). DCs and macrophages, activated for 48 hours with LPS, were similarly stained (solid lines). Filled histograms represent isotype mouse IgG controls. (B) Schematic illustration of the microarray hybridization plan. RNA was isolated from monocytes, macrophages, imDCs, and mDCs for serial microarray hybridization as indicated with arrow lines, after a single round of linear mRNA amplification.21 (C) Hierarchic clustering of monocytes, macrophages, imDCs, and mDCs. Samples were clustered on the basis of their overall similarity using a truncated 578-gene set (see “Data processing and analysis” for selection criteria) and the results visualized using the Treeview program. Red bars indicate up-regulation, whereas green bars indicate down-regulation. Samples self-associated by cell type of origin (monocytes, blue; macrophages, green; imDCs, pink; mDCs, red). imDCs and mDCs lie in a separate branch from monocytes and macrophages.
