HEALTH
New body part found hidden in the lungs
WORDS HARRY BAKER
The newfound cells help maintain a healthy respiratory system
© Getty
Scientists have discovered a brand-new type of cell hiding inside the delicate, branching passageways of human lungs. The newfound cells play a vital role in keeping the respiratory system functioning properly and could even inspire new treatments to reverse the effects of certain smoking-related diseases. The cells, known as respiratory airway secretory (RAS) cells, are found in tiny, branching passages known as bronchioles, which are tipped with alveoli, the small air sacs that exchange oxygen and carbon dioxide with the bloodstream. The newfound RAS cells are similar to stem cells – ‘blank canvas’ cells that can differentiate into any other type of cell in the body – and are capable of repairing damaged alveoli cells and transforming into new ones. Researchers discovered RAS cells after becoming increasingly frustrated by the limitations of relying on the lungs of mice as models for the human respiratory system. To get a better understanding of these differences on a cellular level, the team took lung tissue samples from healthy human donors and analysed the genes within individual cells, revealing the previously unknown RAS cells.