Transcriptional profiling of neutrophil-derived CD14⁺ monocytic cells. FACS-sorted CD15⁺CD54^– neutrophils from G-CSF–mobilized blood were stimulated with GM-CSF (10 ng/mL)/TNFα (25 ng/mL)/IL-1β (10 ng/mL) for 5 days; subsequently, CD14⁺ cells were FACS-sorted (donors A-D). In addition, normal blood monocytes and neutrophils (donors G-F) were FACS-sorted from PB. RNA from CD15⁺CD54^– neutrophils (day 0; starting population; CD54^–), CD14⁺ monocytic cells (day 5; CD14⁺), monocytes (day 0; Mo), and neutrophils (day 0; Neu) were isolated and processed for hybridization on GeneChip Human 2.0 ST arrays (Affymetrix, Santa Clara, CA). (A) Hierarchical clustering (euclidean dissimilarity/average linkage; standard normalization) of differential expressed genes (P < .005) is shown. (B) Heat map and hierarchical clustering of 75 granulocyte- and monocyte-associated genes showing gene expression levels from low (blue) to high (red).