Peripheral neutrophil count and peritoneal neutrophil influx after thioglycollate administration. +/+ or P−/− bone marrow cells were transplanted (⇒) into irradiated +/+ or P/E−/− recipients. Mice were allowed to recover for 4 weeks before being challenged with thioglycollate for 6 hours. Blood cell counts were obtained with a Coulter counter, and (A) the absolute neutrophil number/μL was determined from Wright-stained smears. Nucleated cell numbers were also determined by Coulter counter on lavage fluids from the peritoneum, and (B) the neutrophil number per lavage was calculated from differential counts performed on Wright-stained cytospin preparations; n = 7 to 8. *P < .0005 versus wild type.