Lung sections stained with PAS (A) and Sirius red (B),
respectively. PAS staining to identify mucin-containing cells (purple, top
panel); Sirius Red staining of lung sections depicts peri-bronchiolar and
perivascular collagen (red, bottom panel), original magnification x40; Scale bar
= 50 μm, representative photomicrographs are shown. (C)
Scoring of lung sections stained with periodic acid-Schiff. (D)
Quantitative image analysis of sub-epithelial peri-bronchiolar collagen density
determined by measuring Sirius red-stained collagen in lung sections under
polarized light; data was normalized to AdC PBS control and expressed as percent
(%) increase. Data shown represent means ± s.e.m. from two individual
experiments *P < 0.05, WT compared with IRF5-/- animals by
Mann-Whitney test. Box and whisker plots represent the mean, IQR and minimum and
maximum values. Data were generated from three independent experiments;
n=10-15 per group.