Differentiated DE cells do not express extraembryonic markers.

<p>Embryoid Bodies (EBs) were treated with Activin A (A) and BMP4 (B) for a 6 day period. Sections of treated and untreated EBs were made at days 4 and 6 of the differentiation protocol. (<b>A</b>) Top panels (a–d) show sections obtained from treated (A+B) and untreated (N/A) EBs stained for the extraembryonic marker Sox7. Bottom Panels (e–i) show counterstaining with the nuclear marker DAPI. (<b>B</b>) Top panels (a–d) show sections obtained from treated (A+B) and untreated (N/A) EBs stained for the definitive endoderm marker Sox17. Bottom Panels (e–i) show counterstaining with the nuclear marker DAPI. Data are representative of triplicate experiments.