Fig. 4

Differentiation of pluripotent cells into definitive endoderm cells. a Expression of genes characteristic for definitive endoderm (CXCR4, FOXA2, SOX17) for examined differentiation protocols relative to undifferentiated iPSC samples. For the differentiation experiments cells were maintained in basal medium (RPMI-1640) with Activin A and CHIR99021 for 24 h, and in medium with Activin A alone for the next 48 h. In addition, the media contained: DE1—foetal bovine serum, DE2—human serum, DE3—insulin, transferrin and sodium selenite, DE4—albumin, insulin, transferrin, defined lipids concentrate and ascorbic acid. b Results of immunocytochemical analysis of the generated definitive endoderm cells showing cells positive for CXCR4 and SOX17 markers, and clusters of cells displaying E-cadherin expression. Cells were prepared as described in a. Scale bar 50 µm