Figure 4. Comprehensive analysis of gene expression of third passage cells.

An oligo microarray was used for analysis. After a 28-day culture of second passage cells, total RNA was extracted from trypsinized cells. Representative genes were selected to show heat maps. Specific markers are divided into four groups, including hepatocyte-specific, cytochrome P450s, stem/duct cell-related markers and hepatic transporters. CD44, CD44-positive cells sorted from primary SH colonies; P3, third passage cells; Mat, third passage cells treated with Matrigel-overlay for a week after 14-day culture of second passage cells; MH, mature hepatocytes. To obtain third passage cells, second passage cells were cultured for 28 days with or without Matrigel-overlay and then dissociated cells were collected.