Fig. 2.
(A) Neutrophil migration into the peritoneal cavity after thioglycollate challenge. At indicated time points after intraperitoneal thioglycollate injection, peritoneal cells were harvested by lavage, counted, and cytospins stained for differential counting. Results are represented graphically, showing the migration of neutrophils into the peritoneal cavity over time after thioglycollate stimulus. (○) Represent wild-type neutrophils; (•) represent C/EBPɛ-deficient neutrophils. An asterisk (*) indicates significantly increased numbers of wild-type neutrophils at 4 hours, compared with C/EBPɛ-deficient neutrophils (P < .001, Mann Whitney U). (B) CD11β expression on peritoneal neutrophils after thioglycollate challenge. Mice received thioglycollate intraperitoneally, and neutrophils were harvested at indicated time points. Cells were doubly stained with Gr-1(FITC) and CD11b(PE) and assessed by flow cytometry. Results are represented graphically, by geometric mean of fluorescent intensity. (○) Represent wild-type neutrophils; (•) represent C/EBPɛ-deficient neutrophils. CD11β staining is significantly decreased on C/EBPɛ-deficient neutrophils compared with wild-type cells (P < .004, Mann Whitney U) at 4 hours. By 24 hours, however, CD11β staining is more intense on C/EBPɛ-deficient cells (P < .004), compared with wild-type. CD11b staining of peripheral blood neutrophils is shown at time = 0. (C) CD11b expression on PMA-stimulated peripheral blood neutrophils. Peripheral blood neutrophils were stimulated with PMA, stained with -Gr-1 (PE) and -CD11b (FITC), and examined by flow cytometry. Results are represented by box and whisker graph, showing mean, standard deviation, and standard error of fluorescent intensity. (▪) Represent wild-type neutrophils, gray boxes represent C/EBPɛ-deficient neutrophils. (D) L-selectin (CD62L) expression on peritoneal neutrophils after thioglycollate challenge. Peritoneal lavage cells were harvested at indicated time points and doubly stained with Gr-1(FITC) and anti-mouse CD62L(PE) and assessed by flow cytometry. Results are represented graphically, by geometric mean of fluorescent intensity. (○) Represents wild-type neutrophils; (•) represents C/EBPɛ-deficient neutrophils. Circles graphed at 0 hours represent data obtained from circulating neutrophils from nonchallenged mice (P < .001, Mann Whitney U). L-selectin staining is significantly increased on C/EBPɛ-deficient neutrophils compared with wild-type cells (P< .04, Mann Whitney U) at 4 hours. By 24 hours, however, L-selectin expression is higher on wild-type neutrophils (P < .02, Mann Whitney U) compared with C/EBPe-deficient neutrophils.