Figure 1.

Two human pluripotent stem-cell induction methods into pituitary hormone-producing cells. (a) In the 2D induction method (monolayer culture), endogenous or exogenous BMP-4 signaling promotes non-neural ectodermal lineage. Then, treatment with surrounding factors that emerges in the physiological developmental process (sonic hedgehog (SHH) and fibroblast growth factor (FGF)-8 and -10) promotes the differentiation into pituitary progenitor and hormone-producing cells. (b) In the 3D induction method (organoid culture), oral ectoderm and hypothalamus are simultaneously induced in one cell aggregate. This simultaneous induction of two different tissues can recapitulate the tissue interactions between them, leading to the self-organization of pituitary progenitor cells and subsequent hormone-producing cells.