Differentiation of rat bone marrow cells cultured on artificial basement membrane containing extracellular matrix into a liver cell lineage.

Background/aims: Bone marrow (BM) cells have been shown to be capable of differentiating into a liver cell lineage in vitro. However, their differentiation and proliferation is poor, and the cell characteristics are poorly understood.

Methods: We cultured rat BM cells on an artificial basement membrane containing extracellular matrix (ECM) with hepatocyte growth factor (HGF). The expression of mRNA for liver-specific genes was analyzed by reverse transcription PCR. The expression of albumin and Musashi-1 by cultured cells was analyzed using a fluorescence-activated cell sorter (FACS). The proportions of albumin-positive cells when culture was performed with different concentrations of HGF were analyzed by FACS.

Results: On culture day 21, polygonal cells proliferated and formed cell colonies. These cells expressed mRNA for all the liver-specific genes analyzed, and showed heterogeneous differentiation, some cells expressing albumin, others expressing Musashi-1. Albumin-positive differentiated cells were large and rich in intracellular structures, while Musashi-1-positive undifferentiated cells had the opposite characteristics. Culturing cells with higher concentrations of HGF induced an increased proportion of albumin-positive cells.

Conclusions: The results suggest that cell culture on an ECM with a high concentration of HGF increases the extent to which BM cells differentiate into a liver cell lineage and proliferate in vitro.