In vitro differentiation of rat bone marrow mesenchymal stem cells into hepatocytes

BACKGROUND/AIMS: To investigate the mechanism and regulation of differentiation from bone marrow mesenchymal stem cells (BMSCs) into hepatocytes and to find a new source for therapies of hepatic diseases.

METHODOLOGY: We isolated BMSCs for subsequent differentiation in the presence of hepatocyte growth factor (HGF) or beta-nerve growth factor (beta-NGF). Cell morphology was observed and cell surface phenotypings were detected by flow cytometry. a1-antitrypsin (AAT) expression of the hepatocytes was confirmed by immunocytochemistry and albumin expression was validated by real time PCR and western blotting. The expression of high-affinity nerve growth factor receptor (TrkA) and the activation of Erk pathway were detected by western blotting. Hepatocyte functional activity was confirmed by uptake of indocyanine green (ICG) assay.

RESULTS: Small round cells appeared in the presence of HGF on day 10 or beta-NGF on day 12. Differentiated cells expressed albumin and had functional characteristics of hepatocytes, such as uptake of ICG. BMSCs were positive for TrkA. HGF and beta-NGF significantly upregulated the protein levels of phospho-Erk.

CONCLUSIONS: BMSCs could differentiate into hepatocytes in the differentiation media including HGF or beta-NGF. Combination of HGF and beta-NGF significantly increased the efficiency of hepatic differentiation.