Scientists at Brigham and Women's Hospital (BWH) have identified a human lung stem cell that is self-renewing and capable of forming and integrating multiple biological structures of the lung including bronchioles, alveoli and pulmonary vessels.
The discovery provides new hope for development of new clinical treatments for those with lung disease for which no therapies exist.
"This research describes, for the first time, a true human lung stem cell. The discovery of this stem cell has the potential to offer those who suffer from chronic lung diseases a totally novel treatment option by regenerating or repairing damaged areas of the lung," said Piero Anversa, director of the Center for Regenerative Medicine at Brigham and Women's Hospital and corresponding author.
Using lung tissue from surgical samples, researchers identified and isolated the human lung stem cell and tested the functionality of the stem cell both in vitro and in vivo.
Once the stem cell was isolated, researchers demonstrated in vitro that the cell was capable of dividing both into new stem cells and also into cells that would grow into various types of lung tissue.
Next, researchers injected the stem cell into mice with damaged lungs. The injected stem cells differentiated into new bronchioles, alveoli and pulmonary vessel cells that not only formed new lung tissue, but also integrated structurally to the existing lung tissue in the mice.
The researchers defined this cell as truly "stem" because it fulfills the three categories necessary to fall under stem cell categorization: first, the cell renews itself; second, it forms into many different types of lung cells; and third, it is transmissible.
This study has been published in the May 12, 2011 issue of the New England Journal of Medicine.