Self-renewing human lung stem cells have been identified for the first time in a discovery that could offer important clues for treating chronic lung diseases. Previous studies have shown researchers were able to create lung cells using human embryonic stem cells, but this lung stem cell was isolated using surgical samples of adult human lung tissue.
“This research describes, for the first time, a true human lung stem cell,” said co-author Piero Anversa, director of the Centre for Regenerative Medicine at Brigham and Women’s Hospital in Boston, U.S.
“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.”
Reporting in the New England Journal of Medicine the researchers found that human lungs contain undifferentiated human lung stem cells nested away in niches in the distal airways, which are less than 2 mm in diameter. Using lung tissue from surgical samples, they 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, the 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, they injected the stem cell into mice with damaged lungs. The injected stem cells differentiated into new bronchioles, alveoli and pulmonary vessel cells which not only formed new lung tissue, but also integrated structurally to the existing lung tissue in the mice.
“These are the critical first steps in developing clinical treatments for those with lung disease for which no therapies exist,” said co-author Joseph Loscalzo, chair of the BWH department of medicine.