The IL-8–induced mobilization in decontaminated mice is restored after oral administration of endotoxins. Mice were receiving either normal drinking water (n = 7); drinking water containing endotoxins (33 mg/L) and saccharose (20 mg/L) (n = 8); drinking water containing 125 mg/L ciprofloxacin, 500 mg/L metronidazol, and 20 mg/L saccharose (n = 7); or water containing 125 mg/L ciprofloxacin, 500 mg/L metronidazol, 20 mg/L saccharose, and endotoxins (n = 7). After one week of treatment, mice were mobilized with a single intraperitoneal injection of PBS containing 1% bovine serum albumin or 30 μg IL-8. At 20 minutes after the injection, mice were killed and blood and bone marrow were obtained. Results are expressed as means ± SD. *P < .05 compared with the controls.