Normal infiltration of eosinophils in lung tissues ofeotaxin^−/− mice challenged with ovalbumin. (A) Inflammation scores of lung tissues of wild-type (+/+) and eotaxin null (−/−) mice at different time points after ovalbumin challenge. Inflammation severity was scored to account for different infiltrated cell types with 0 as the least and 4 as marked inflammation. (B) Quantification of eosinophils in lung tissues of wild-type (+/+) and eotaxin null (−/−) mice at different time points after aerosol challenge. Data represent the mean ± SEM of eosinophils from 6 to 8 high-power fields for each mouse; n = 7 for both +/+ and −/− at 6 hours; n = 4 for both +/+ and −/− at 12 hours; n = 6 for +/+ and n = 8 for −/− at 24 hours. (C) Quantification of different cells recovered from the BAL fluid of wild-type (+/+) and eotaxin null (−/−) mice at 18 hours after OVA aerosol challenge. Data represent the mean ± SEM of cells; n = 5 for wild-type and n = 6 for eotaxin null mice. (D) Northern blot analysis of total lung RNA from untreated and OVA-challenged wild-type mice. The blot was probed with ³²P-labeled mouse eotaxin cDNA (upper panel), stripped, and tested with a probe specific for mouse GAPDH (bottom).