Fig. 2.

Cultured bovine blastocyst-derived trophoblast colonies retain form and function of the trophectoderm. (A,B) Trophoblast colonies were positive for CDX2, a transcription factor considered a marker for this lineage, known to play an important role in trophectoderm development. (C,D) Trophoblast colonies also showed existence of a complex network of cytokeratin, an arrangement that enables the trophectoderm to resist mechanical stress. (E–G) Cytoplasmic lipid droplets in the blastocyst-tropectodermal layer are abundant (stained by Nile Red), and indicative of cellular homeostasis linked to energy storage and lipid metabolism. (H–J) Lipid droplets were also prominent in cultured trophoblast colonies indicating maintenance of metabolic properties. For all panels, cell nuclei are counterstained with DAPI.