A*STAR scientists find key to lung regeneration

PHOTO: A*STAR scientists find key to lung regeneration

SINGAPORE - A*STAR scientists have identified and characterised the adult stem calls that have the ability to regenerate lung tissue, opening the way to understanding lung regeneration.

The breakthrough discovery, jointly led by Dr Frank McKeon from Genome Institute of Singapore (GIS) and Dr Wa Xian from Institute of Molecular Biology (IMB), found that adult stem cells will only differentiate into the specific cell type they originated from.

The team cloned adult stem cells from three different parts of the lungs: nasal epithelial stem cells, tracheal airway stem cells and distal airway stem cells.

Although all three cell types are 99 per cent identical, the team found that only distal airway stem cells (DASCs) formed alveoli to replace and repair damaged lung tissue. This is as alveolar cells are found only in the distal airways, Dr Wa explained.

The team then infected mice with a powerful strain of H1N1 influenza virus, and found that DASCs rapidly multiplied and migrated to the influenza-damaged lung areas.

These cells formed "pods" which matured into new alveoli to replace the damaged alveoli, leading to lung regeneration.

Alveoli are tiny air sacks in the lungs, an essential component of the lungs which help to replace carbon dioxide in red blood cells with oxygen.

These findings hold key information that may in the future be used to develop drugs for the boosting of cell regeneration of the lungs and airways.

The research was done in collaboration with scientists from the National University of Singapore (NUS), clinicians from Harvard Medical School and the Brigham and Women's Hospital in Boston.

Professor Birgitte Lane, executive director of IMB, applauded the findings as a "fine example of collaborative research" which has brought "new insight into lung epithelial stem cells."

Lung damage can be caused by influenza infections, which can induce acute respiratory distress syndrome, and chronic respiratory diseases such as chronic obstructive pulmonary disease (COPD).

Acute respiratory distress syndrome has a death rate of up to 50 per cent and COPD is the fifth biggest killer worldwide.