Liver-specific gene expression in mesenchymal stem cells is induced by liver cells

Figure 6 Gene expression profile. Cultured rMSC, hepatocytes (rHep), and GFP+ or GFP- cells of the cocultures after 1-3 wk were investigated for their expression of the stem cell marker Thy1 (A) and of the liver specific markers AFP (B), CK-19 (C), CK-18 (D), or albumin (E). Results from one out of three experiments are shown. rMSC (lane rMSC), GFP- (lane GFP- cocultures) or GFP+ (lane GFP+ cocultures) cells showed a stable Thy1 gene expression over the whole observation period, whereas hepatocytes (lane rHep) showed no signal for Thy1 gene expression in the RT-PCR analysis (A). In cultures of hepatocytes, GFP- or GFP+ cells show, the expression of the studied liver markers was observed, whereas in cultured rMSC none of the studied liver specific genes was observed at all time points (B-E). Cultured hepatocytes expressed AFP and CK-19 weakly (B and C), and CK-18 (D) and albumin (E) stable. GFP- cells from cocultures showed a stable expression of AFP (B), CK-19 (C) or albumin (E), and a weak signal for CK-18 expression (D). The GFP+ cells showed a stable expression of the liver specific genes AFP (B), CK-18 (D), and albumin (E), and a weak expression of CK-19 (C) over the whole observation period.