Lung Cells Grown for First Time with Human Stem Cells

Columbia University Medical Center researchers report they have succeeded in transforming human stem cells into functional lung and airway cells.

The breakthrough, a medical first, is reported in the journal Nature Biotechnology. The researchers behind the work say it has the potential for significant advances in modeling lung diseases, studying lung development, and ultimately, for creating lung tissue to be used in transplantation.

"Researchers have had relative success in turning human stem cells into heart cells, pancreatic beta cells, intestinal cells, liver cells, and nerve cells, raising all sorts of possibilities for regenerative medicine," said study leader Dr. Hans-Willem Snoeck. "Now, we are finally able to make lung and airway cells. This is important because lung transplants have a particularly poor prognosis. Although any clinical application is still many years away, we can begin thinking about making autologous lung transplants-that is, transplants that use a patient's own skin cells to generate functional lung tissue."

Snoeck and his team's work builds off a prior advance that enabled them to turn either embryonic or pluripotent stem cells into the precursors of lung and airway cells known as anterior foregut endoderm.

Embryonic stem cells, when taken from humans, come with a air of controversy, although human-induced pluripotent stem cells, which are generated form human skin cells by coaxing them into taking a developmental step backwards, tend to be less controversial. The researchers were able to create functional lung and airway cells from both types of stem cells.

The current study highlights new factors that can complete the transformation of human embryonic or induced pluripotent stem cells into the cells that cover the lung surface known as functional lung epithelial cells.

At least six types of epithelial cells were generated, but the researchers were particular in noting the creation of type 2 alveolar epithelial cells, which are important in carrying out essential gas exchange as well as in repairing lung injuries or damage.

In patients with lung diseases such as idiopathic pulmonary fibrosis (IPF), in which type 2 alveolar epithelial cells are believed to play a key role, the breakthrough could have significant implications.

"No one knows what causes the disease, and there's no way to treat it," Dr. Snoeck said. "Using this technology, researchers will finally be able to create laboratory models of IPF, study the disease at the molecular level, and screen drugs for possible treatments or cures."

"In the longer term, we hope to use this technology to make an autologous lung graft," Dr. Snoeck said. "This would entail taking a lung from a donor; removing all the lung cells, leaving only the lung scaffold; and seeding the scaffold with new lung cells derived from the patient. In this way, rejection problems could be avoided."