IL-25 signaling in CD11c+ cells increases HDM-induced collagen deposition and airway resistance. (A) Representative lung sections of HDM or PBS treated WT and mutant mice, as indicated, stained with Picro red for collagen deposition. (B) Quantification of collagen deposition. Area, integrated density and background values were obtained using Image J software (Corrected intensity= integrated density-(area × mean of the background)). All data were normalized against WT PBS control. Significance indicated for HDM-treated WT vs KO mice. (C) Airway hyper-resistance response to methacholine in HDM or PBS treated WT or mutant mice as indicated. Data are the mean ± sem of two independent experiments with two or three fields per mouse counted with total of n=4–6 mice per group (A,B) and (C) three independent experiments with a total of n=7–8 mice per group, except one experiment for CIKS CD11c KO with n=3 mice. *p<0.05; **p<0.01.