Inhibition of neutrophil mobilization by blockade of G-CSF is abrogated by administration of AMD3100. Anti–G-CSF–blocking antibody (150 μg) and AMD3100 (100 μg) alone or in combination were administered intraperitoneally 20 minutes before intraperitoneal injection of 3% TG. The number of neutrophils per milliliter of blood (A) and the number of neutrophils per milliliter of peritoneal lavage fluid (B) were determined 2 hours following TG injection. Results are expressed as means plus or minus SEM (n = 3). *P < .05; **P < .005 (1-way ANOVA and Dunnett test).