Researchers at Children’s Hospital Los Angeles Identify a Key Aspect of Lung Epithelial Progenitor Cell Behavior

Published on 
October 1, 2012



Ahmed El-Hashash, PhD

CONTACT FOR MEDIA:  Ellin Kavanagh, (323) 361-8505

LOS ANGELES (October 1, 2012) –  Investigators at The Saban Research Institute of Children’s Hospital Los Angeles have characterized a key aspect of stem cell behavior using lung epithelial progenitor cells.  The study, by Ahmed El-Hashash, PhD, and David Warburton, DSc, MD, shows that most distal lung epithelial progenitor cells divide and produce one progenitor cell and one differentiated cell in a process called asymmetric cell division. This finding has implications in fetal lung defects and in lung injuries.

“Understanding the behavior of lung stem cells and the mode of their division could identify innovative solutions for restoring normal lung development and repair/regeneration after injury,” said Warburton, director of Developmental Biology and Regenerative Medicine at The Saban Research Institute.

Lung epithelial progenitor cells are stem cells that develop into the lining of the lungs during fetal development. The proper balance of progenitor cells and their progeny is essential for normal lung formation. Lung hypoplasia and bronchopulmonary dysplasia are medical conditions in infants in which the lungs develop abnormally. The causes of these diseases and the inability of the lungs to recover from them have been hypothesized to involve a deficiency of lung epithelial progenitor cells. Such a deficiency may have its root in aberrant asymmetric cell division.

The authors of this study found that a protein called Numb, a determinant of cell fate, is localized to one side of distal lung epithelial progenitor cells and eventually segregated into one daughter cell upon division. Numb causes the daughter cell to differentiate, while the daughter cell that did not receive Numb remains a progenitor cell. Additionally, the investigators found that distal lung epithelial progenitor cells divide asymmetrically over 90% of the time.

“I believe that characterizing asymmetric cell division and identifying novel mechanisms regulating asymmetric cell division and behavior of lung epithelial stem cells can help to identify novel targets for the prevention and rescue therapy of fatal lung disease in infancy and childhood, and for lung regeneration after injury,” said El-Hashash, who is first author on the study and is also an assistant professor at the Keck School of Medicine of the University of Southern California.

The complete findings of this study are published in the current issue of the Journal of Histochemistry & Cytochemistry.

About Children’s Hospital Los Angeles

Children's Hospital Los Angeles has been named the best children’s hospital in California and among the top five in the nation for clinical excellence with its selection to the prestigious U.S. News & World Report Honor Roll. Children’s Hospital is home to The Saban Research Institute, one of the largest and most productive pediatric research facilities in the United States. Children’s Hospital is also one of America's premier teaching hospitals through its affiliation since 1932 with the Keck School of Medicine of the University of Southern California.

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