What exactly causes a healthy lung to become a sick one?
Cystic fibrosis scientists discover abnormal response to lung infections
SASKATOON — Scientists at the University of Saskatchewan say they think they’ve discovered why people with cystic fibrosis are prone to lung infections.
The 18 researchers say they’ve concluded that the genetic mutation that causes cystic fibrosis prevents normal secretion of airway surface liquid, including mucus.
“Airway surface liquid is crucial to kill bacteria because airway surface liquid has antimicrobial properties and is sticky to bacteria, so bacteria gets stuck to it,’’ said lead researcher Juan Ianowski Thursday.
Little hairs called cilia then push the germs out of the airway.
Ianowski, an associate professor in the physiology department at the University of Saskatchewan, and his team developed a technique to look inside the airways of normal pigs and piglets modified to have cystic fibrosis, but in the earliest stage of the disease.
He says there has long been interest in that “window at the very beginning of life where everything’s still quite healthy.’’ The question was, what exactly caused a healthy lung to become a sick one?
“If one were able to identify what that thing is and could stop it, one would wonder if you could stop the disease,’’ he said.
“The inability to kill bacteria has been identified for a long time as a problem, but it was never terribly clear why that was the case.’’
One theory developed many years ago was that airway surface liquid production is abnormal, but there was no way to prove it.
But technology improved. Ianowski says it took seven years to develop the technique needed to see the production of mucus in a living animal — a liquid so thin, it’s about the width of a hair.
The researchers found that the piglets with cystic fibrosis never produced the normal amount of airway surface liquid in their lungs to fight off bacteria, “which means the bacteria will be more likely to remain, to reproduce and to cause infection,’’ said Ianowski.