Mori, M. et al. Nat. Med. 25, 1691–1698 (2019)

Lung transplantation is the only option to treat chronic obstructive pulmonary disease, but many patients cannot receive this treatment due to a shortage of suitable donor organs. Several studies have attempted to generate lungs from pluripotent stem cells (PSCs), but these have been hampered by the difficulty to recreate the structural and functional complexity of the lung in vitro. Using a blastocyste complementation approach, a team of investigators from Columbia University Irving Medical Center, New York was able to rescue lung formation in genetically defective recipient mouse embryos that cannot develop functional lungs by transplanting wild-type PSCs previously cultured in specific conditions. Further work will determine if these results can be translated into larger animal models.