US researchers said they have identified for the first time human lung stem cells that are self-renewing and 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 Piero Anversa, director of the Centre for Regenerative Medicine at Brigham and Women's Hospital and co-author of the study in the New England Journal of Medicine.
"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."
True stem cell
The finding qualifies as a true stem cell because it renews itself; can form different types of lung cells like bronchioles, alveoli and pulmonary vessel cells; and when injected into a mouse it could be isolated and removed and used to treat another mouse with the same results, the study said.
"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.
"Further research is needed, but we are excited about the impact this discovery could have on our ability to regenerate or recreate new lung tissues to replace damaged areas of the lungs."
Stem cell therapy on lung diseases has long been elusive because the lung is a highly complex organ with a variety of cell types that can renew at different rates, experts say.
Lung disease is the third leading killer in the United States after heart disease and cancer, according to the National Institutes of Health.
(Sapa, May 2011)
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