MMP2 and hepatitis A virus infection: In the light of the benefited effects of ADSC transplantation on the histology and serum level of liver fibrosis, we further determined the expression of the hepatic fibrosis-related genes, including alpha smooth muscle actin (α-SMA), collagen type I alpha 1 (COL1A1), matrix metalloproteinase 2 (MMP2), and tissue inhibitor of metalloproteinases 2 (TIMP2), in the liver tissues.