Figure 3

Effect of bleomycin challenge on cathepsin K expression in the lungs of cath K transgenic and wild-type mice. Cathepsin K transgenic mice (black bars) and wild-type mice (white bars) were treated with bleomycin for 14 days (A-E). Mice were then euthanized and BAL cells (A, B), freshly isolated type II alveolar epithelial cells (A, C), lung homogenate (A, D), and concentrated BAL fluid supernatant (E) were prepared for analysis of cath K mRNA by real-time RT-PCR (A) and western blotting (B-E). (A), data are given as fold change in cathepsin K mRNA of bleomycin-challenged cath K tg mice compared to wild-type mice. (F) Gelatin zymography employing concentrated BAL fluid protein from mock- or bleomycin-treated wild-type mice and cath K tg mice. Data are shown as mean ± SD of n = 3 determinations. (B-F), data represent at least n = 3–5 independent analyses. * indicates p < 0.05 versus bleomycin-treated wild-type mice at day 14 post-treatment.