Figure 1.

 Characterisation of human hepatic progenitor cells. (A) Magnetically sorted fetal liver cells, immediately after isolation, stained positive for CD117 and CD34 but negative for CD90, CD45, albumin, and cytokeratin 19 (CK19). (B) CD117+/CD34+/Lin− cells, when cultured on collagen I coated culture dishes, grew in colonies. The first marker to be expressed on some cells was the hepatocyte growth factor receptor (c-Met, green). The nucleus is stained with DAPI (blue). Magnification 40×. (C) Freshly isolated and expanded cells in various passages gave rise to albumin− CK19− (white arrow), albumin+ (green) CK19+ (red), albumin+CK19− (green, hepatocytes), and albumin−CK19+ (red, cholangiocytes). Magnification 60×. (D) Three colour analysis demonstrated that c-Met was expressed on albumin+ and CK19+, but not albumin−/CK19− cells.