Fig. 1

Histological and histochemical analysis of dermal fibrosis in male bleomycin-treated Balb/C, C57BL/6 and DBA/2 mice. a Representative images of H&E-stained sections of male mouse skin treated with subcutaneous NaCl or bleomycin given every other day over a period of 3 weeks. Original magnification ×100. b Dermal thickness of skin harvested from mice treated with NaCl or bleomycin after 3 weeks. Four high-power field images were taken (two measurements per image). Results represent the relative fold-change compared to NaCl-treated control mice. All values represent means ± standard error of the mean (SEM); n = 6 in each group. c Representative images of second harmonic generation imaging of type I fibrillary collagen in mouse skin harvested after 3 weeks of treatment with NaCl or bleomycin injected every other day. Note different distribution of fibre alignment and intensity in NaCl- and bleomycin-treated samples. Note that all images were acquired with the same excitation power. Original magnification ×250. d Hydroxyproline assay: results are represented as means ± SEM of triplicate measurements obtained from six mice (two biopsies per mouse) and shown as relative fold-change compared to NaCl-treated control samples. e Representative images of alpha smooth muscle actin (α-SMA) immunohistochemical analysis. Original magnification ×200, inset ×630. f Relative number of α-SMA-positive cells in the dermis of NaCl- or bleomycin-treated mice. Results represent the relative fold-change compared to NaCl-treated control mice. All values represent means ± SEM; n = 6 each group. n.s. not significant