Quantification of Pulmonary Fibrosis in Mice

The left lung of the mice was fixed in formalin for 48 h, then dehydrated, embedded and sectioned. Then, lung sections (4 μm) were prepared and stained with hematoxylin–eosin (H&E) and Masson’s trichrome. Quantification of pulmonary fibrosis was performed as described previously [45 (link)]. In brief, images were photographed with an upright transmission fluorescence microscope (Olympus) and analyzed by Image-Pro Plus Version 6.0 (Media Cybernetics, Inc, American). The software selection tool can select the entire lung tissue area and automatically calculate the total pixels, P_w, of the region. It can then use the same method to calculate the total pixels, P_f, of the fibrosis region (fibrosis ratio = fibrosis area total pixel, P_f/total lung total pixel, P_w).