Figure 3.

Granulocytes in C/EBPɛ −/− mice are not functional. Oxidative burst was measured in granulocytes by the conversion of DHR to fluorescent rhodamine-123 (which occurs with PMA stimulation in the presence of reactive oxygen intermediates) and assayed by flow cytometry. White cells from C/EBPɛ +/+ and −/− mice were analyzed, with a total of 10,000 cells gated in both samples (A). PMA stimulation of cells demonstrated no oxidative burst in the C/EBPɛ −/− cells, as seen in the +/+ cells (thick line, PMA-stimulated cells; thin line, unstimulated). Wright–Giemsa stain shows atypical hyposegmented neutrophils are present in the peripheral blood of −/− mice (A). Following TGC-induced peritonitis, DHR assays were performed on the peripheral blood (B) and peritoneal exudate of +/+ and −/− littermates (C and D). Myelocytes, metamyelocytes, and a significantly reduced number of band neutrophils in the −/− mice are noted, compared with 85% segmented neutrophils seen in the +/+ littermates (smears, B–D) in both the peritoneal fluid and peripheral blood. Arrows show peritoneal macrophages. Arrowhead shows basophil.