Fig. 1

Time line of apoptosis in the model of bleomycin (BLM)-induced lung fibrosis. Hematoxylin and eosin (HE) staining (× 200) (a); Sirius Red staining (collagen fibers identified by red staining; × 200) (b); TUNEL staining (× 200) (c); cleaved caspase 3 staining (× 200) (d), inlets show higher magnifications (× 400), arrows highlight apoptotic cells; Ashcroft scores (e); semi-quantification of TUNEL+ cells (f) and semi-quantification of cleaved caspase 3+ cells (g): n = 4 (saline) or n = 6–9 (BLM). Data in box plots are expressed as median (line), mean (+) and minimum and maximum values: *p < 0.05, **p < 0.01, ***p < 0.001, Mann-Whitney U test. Scale bars 50 μm and 20 μm for inlets