Generation of lung organoids from human pluripotent stem cells in vitro

The lung epithelium is derived from the endodermal germ layer, which undergoes a complex series of endoderm–mesoderm-mediated signaling events to generate the final arborized network of conducting airways (bronchi, bronchioles) and gas-exchanging units (alveoli). These stages include endoderm induction, anterior–posterior and dorsal–ventral patterning, lung specification, lung budding, branching morphogenesis, and, finally, maturation.