Fig. 5.

Periostin-deficient (periostin^−/−) mice are protected from bleomycin-induced fibrosis after 14 days. Wild-type (WT) littermates and periostin^−/− mice were injected intratracheally with 0.025 U of bleomycin or 50 μl of saline. At 14 days, lungs were harvested for hydroxyproline assay and histology. A: hydroxyproline levels in wild-type mice treated with bleomycin are increased, but periostin^−/− mice are protected from increased collagen production (n ≥ 4/group representative of 2 experiments). *P < 0.05, **P < 0.01. B: histology showing WT mice treated with saline or bleomycin and periostin^−/− mice treated with bleomycin. H&E, hematoxylin-eosin. Images are representative sections from 3 mice/group.