It was only a couple of years ago that researchers starting making progress in identifying and cataloging the stem cell populations in lung tissue. Last year researchers mapped out some of the cellular path of development for lungs in embryos. Here they are building on that to grow lung cells from embryonic and induced pluripotent stem cells, which opens the doors to the next stage of lung tissue engineering development.
"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. 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."
The research builds on [the] 2011 discovery of a set of chemical factors that can turn human embryonic stem (ES) cells or human induced pluripotent stem (iPS) cells into anterior foregut endoderm - precursors of lung and airway cells. In the current study, [researchers] found new factors that can complete the transformation of human ES or iPS cells into functional lung epithelial cells (cells that cover the lung surface). The resultant cells were found to express markers of at least six types of lung and airway epithelial cells, particularly markers of type 2 alveolar epithelial cells. Type 2 cells are important because they produce surfactant, a substance critical to maintain the lung alveoli, where gas exchange takes place; they also participate in repair of the lung after injury and damage.