Immunofluorescence Analysis of αSMA

Immunofluorescence analysis was performed as previously described (Lucarini et al., 2014 (link)). Briefly, histological sections of 5 μm thick were deparaffinized and boiled for 10 min in sodium citrate buffer (10 mM, pH 6.0, Bio-Optica, Milan, Italy) for antigen retrieval. A pre-incubation in 1.5% bovine serum albumin (BSA) in PBS, pH 7.4 for 20 min at RT was necessary to minimize the unspecific binding; whereupon, the sections were incubated overnight at 4°C with rabbit monoclonal anti-αSMA antibody (1:200 ABCAM, USA) followed by goat anti-rabbit Alexa Fluor 488-conjugated IgG (1:300 Invitrogen, San Diego, CA, USA) for 2 h in the dark at RT. Negative controls were performed with non-immune rabbit serum substituted for the primary antibody. The counterstaining of nuclei was obtained with 4′,6-diamidino-2-phenylindole (DAPI). Representative images were acquired with an Olympus BX63 microscope coupled to CellSens Dimension Imaging Software version 1.6 (Olympus, Milan, Italy). αSMA expression was quantified by densitometric analysis of fluorescence signal intensity, measured on digitized images using ImageJ software². Twenty regions of interest (ROI) were evaluated for each sample. Values are expressed as mean ± SEM of the OD measurements (arbitrary units) of individual mouse from the different experimental groups.