( ng growth and ultimately lung function ...)Group proves it's possible to grow new lung alveoli by growing new blood vessels

Doing that involved a new gene therapy technique, explains Dr. Thébaud. Knowing that a particular protein, VEGF, a vascular endothelial growth factor, is crucial for the normal development of the lung, and that angiopoeitin-1, another angiogenic growth factor is crucial for blood vessel maturation, the team attached the proteins to an adenovirus and administered it through an aerosol directly into the lungs. In effect, the virus carried the protein to the heart of millions of lung cells. Once inside the cells, the growth factor proteins went to work doing the job they were programmed to do.

The results were striking: In microscopic images, the scientists have charted the growth of alveoli and lung capillaries. In a typically healthy lung, a complex network of capillaries encircles the alveoli. Oxygen flows from the lungs through ultra-fine epithelial and endothelial tissues into the blood; carbon dioxide diffuses from the blood into the alveoli. In an infant's underdeveloped lungs, the alveoli are larger and fewer and there are fewer developed capillaries. It's a condition that leaves them gasping--and one that is shared by people who have emphysema.

"At this stage it's simply proof of principle," says Dr. Thébaud, also a pediatrician at the Stollery Children's Hospital's Neonatal Intensive Care Unit. The next step is to prove it's possible to replicate safely in larger mammals. Once that's done, it's possible the concept--growing blood vessels to cure a disease that is traditionally thought of as an airway disease--could be tested clinically in people.