Abstract:

BACKGROUND: Mobilizing autologous or extraneous bone marrow-derived liver stem cells may promote liver regeneration, however, its safety before the large scale clinical application needs further evaluation.

OBJECTIVE: Bone marrow-derived liver stem cells (BDLSCs) were induced by culturing the rat bone marrow mesenchymal cells in the medium containing 5% cholestatic sera, and then were implanted into nude mice to observe the tumorigenicity.

METHODS: Rat bone marrow mesenchymal cells (BMSCs) were isolated and incubated in the medium containing 5% cholestatic sera. Immunofluorescent stain was used to detect the expression of albumin, alpha-fetoprotein and cytokeratin18 by the cultured cells. Glycogen and urea synthesis by these cells were analyzed, respectively. BDLSCs following 14 days of culture were incubated in the skin of nude mice to observe neoplasia in local site.

RESULTS AND CONCLUSION: Rat BMSCs survived in the medium containing 5% cholestatic serum and formed into small colonies on the fourth day after culture. Seven days later, the colonies expanded and there appeared some polygonal cells in the peripheral area. About 14 days later, these polygonal cells were confluent and presented the shape of cobblestone. Immunofluorescent stain showed that these cells expressed cytokeratin18, albumin and alpha-fetoprotein. Staining for glycogen displayed that glycogen granules were seen in cells. From 12 to15 days after culture, urea nitrogen concentrations in the medium were gradually increased. Rat BDLSCs were incubated in the skin of nude mice. Thirty days later, no neoplasia was found in the local site, and the tissue structure was normal. This result indicated that rat BDLSCs induced with the medium containing 5% cholestatic serum might have not tumorigenicity.