Differentiation of VAL9 hESCs into hepatic progenitors. a Stages of differentiation and phase contrast microscopy images showing corresponding cell morphology. b Representative images of immunofluorescence from definitive endoderm. Cells express GATA binding protein (GATA)4, SOX17, hepatic nuclear factor (HNF)3β and are negative for human octamer-binding transcription factor (OCT)4 and homeobox transcription factor (NANOG), two markers characteristic of undifferentiated cells. c Representative fluorescence-activated cell sorting (FACS) analysis of VAL9 at endoderm stage where 98.4 % cells were CXCR4-positive. d Representative immunofluorescence of hepatic progenitors. Cells express GATA4, HNF4α, HNF6, HNF3β, cytokeratin (CK)19 and AFP. e Representative FACS analysis of VAL9 at hepatic progenitor stage where 97 % cells were epithelial cell adhesion molecule (EpCAM)-positive.