Identification of culture conditions for inducing neuroectoderm and mesendoderm differentiation in CDM-BSA.

H9 hESCs were grown for different periods in CDM-BSA supplemented with different growth factors (Activin, FGF2 or BMP4) or chemical inhibitors [SB431542 (SB) for Activin/Nodal, SU5402 (SU) for FGF or BIO for GSK3β/Wnt]. Then, immunostaining analyses were used to determine the fraction of cells expressing the pluripotency marker Oct-4, the neuroectoderm marker Sox2, the mesoderm marker Brachyury, and the endoderm marker Sox17. The levels of marker-expressing cells were divided into five arbitrary categories: 0 for absence of expression, Very Low (VL) for <1% expressing cells, Low (L) for <5% expressing cells, Moderate (M) for >10% expressing cells, High (H) for >50% expressing cells. Indicated in blue are conditions allowing the generation of neuroectoderm (expressing Sox2) and in red those inducing mesendoderm (cells expressing Brachyury or Sox17).