4.3 Histological analysis
The liver tissues were fixed in 4% paraformaldehyde, embedded in paraffin and prepared into 5 μm sections. And then the Hematoxylin and eosin (HE) staining, Masson’s Trichrome Staining and Sirius red staining were applied to stain the above sections referring to the standard procedure of the manufacturer. The liver fibrosis score was determined by Sirius red staining and based on the METAVIR classification method (F0 = no fibrosis, F1 = portal fibrosis without septa, F2 = portal fibrosis with few septa, F3 = numerous septa without cirrhosis, and F4 = cirrhosis)19.