Rewriting the textbooks on lung development
Look in any medical textbook and you'll be told that our lungs only produce air sacs (called alveoli) until the age of about three. After that, it was assumed that the existing alveoli grew larger as our lungs grew, but no new air sacs were formed. However, an international team of researchers led by the University of Leicester has found that our lungs continue to grow new alveoli well into adolescence.
The researchers from our Department of Infection, Immunity and Inflammation enlisted the help of the University of Nottingham to measure the size of alveoli in participants' lungs. The participants inhaled helium and then held their breath whilst their lungs were imaged by a magnetic resonance (MR) machine. The helium gas helped measure the precise size of the alveoli. The researchers found that adults' alveoli were almost the same size as children's - they simply had more of them, meaning the lungs had grown extra air sacs as they grew older.
Dr. Manjith Narayanan, one of the leaders on the study, believes the results challenge the established position that the lungs cannot grow new alveoli past the age of three. The findings have important implications for understanding how our lungs can potentially heal after injury and the effects of air-borne pollutants.
The research was carried out by the Universities of Leicester, Nottingham and Bern and funded by the Wellcome Trust. The findings are published in the American Journal of Respiratory and Critical Care Medicine.
- University Press Release
- Alveolarization continues during childhood and adolescence: new evidence from 3He magnetic resonance, in American Journal of Respiratory and Critical Care Medicine