Figure 3.

Stepwise differentiation of Nkx2.1+ lung progenitors from human induced pluripotent stem cells (iPSCs). (A) Schematic strategy and time line to generate Nkx2.1+ lung multipotent progenitors from human iPSCs. (B) High yield of definitive endoderm from CF1 RNA-induced pluripotent stem cells (RiPSCs) was obtained after treatment for 4 days in RPMI-1640 medium in the presence of 2% B27 supplement, Activin A (100 ng/ml), and 5 μM PI3 kinase inhibitor LY294002 with more than 90% of cells coexpressing transcription factors SOX17 and FOXA2. Scale bar = 200 μm. (C) Anteriorization of endoderm into foregut endoderm cells with SOX2 expression in Foxa2+ cells derived from CF1 RiPSCs after 4 days of treatment with 500 nM A-83–01 (TGF-β antagonist) and 100 ng/ml Noggin (bone morphogenetic protein [BMP]4 antagonist). Scale bar = 100 μm. (D) Confocal image after immunofluorescence staining showing that some Nkx2.1+ spheres contain basal cells positive for p63. Scale bar = 40 μm. Adapted by permission from Reference 105.