Histological Analysis of Tissue Samples

The collected tissues were fixed in 4% paraformaldehyde (PFA, Servicebio, China), dehydrated with gradient alcohol series and embedded in paraffin. The embedded samples were cut into 6-µm-thick sections for hematoxylin and eosin (H&E) staining and Masson’s trichrome staining. Immunofluorescence (IF) staining was carried out as previously described [18 (link)]. The collected samples were fixed in 4% PFA, dehydrated with gradient series of sucrose and embedded in OCT. Ten-micrometer thick sections were incubated with primary antibodies, including those targeting AE1/AE3 (1:100; Thermo Fisher, USA, 53-9003-82), CD31 (1:100; Novus, Germany, JC/70A), and α-SMA (1:200; Abcam, UK, ab7817). Then, the sections were incubated with secondary antibodies at room temperature for 1 h. Fluorescence images were clearly observed under a Leica DM6B microscope.