Generation of organized anterior foregut epithelia from pluripotent stem cells using small molecules

Anterior foregut endoderm (AFE) gives rise to many tissue types of interest for therapeutic research including the esophagus, salivary glands, lung, thymus, parathyroid and thyroid. Despite its importance, only few reports describe the generation of AFE from pluripotent stem cells (PSCs) by directed differentiation. Here, we describe a novel protocol to derive a subdomain of AFE, identified by expression of Pax9, from PSCs using small molecules and chemically defined conditions. Generation of a reporter PSC line allows isolation and characterization of Pax9+ AFE cells. When transplanted in vivo, Pax9+ AFE can form several distinct types of complex anterior foregut epithelia including mucosal glands and stratified squamous epithelium. Finally, we show that the directed differentiation protocol can be used to generate AFE from DiGeorge Syndrome patient-specific human induced PSCs, thus creating a platform to produce anterior foregut derivatives for therapy and to enable the study of disorders of the AFE. Total RNA obtained from FACS purified from in vitro dervied mouse definitive endoderm, anterior foregut and ES cells. AFE cells were derived from a 129X1/SvJ background, DE cells from 129X1/SvJ x 129S1/SV-+p+Tyr- cKitlSl-J/+ (R1 ES cells) and non reporter ES cells from a 129P2/OlaHsd background.