MMP9 and infection: The qRT-PCR results showed that the mRNA expression levels of related molecules in liver fibrosis, such as α-SMA, collagen-1, collagen-3, mmp9, timp1 and TGF-β1, in liver tissue were significantly decreased in the immune group compared with the infection group (t = 8.684, 4.973, 9.545, 4.104, 5.371 and 6.575, all P < 0.05) (Fig. 3e–j), indicating significant inhibition of HSCs activation in the liver.