Discovered a completely new type of cell hidden inside the lungs

Scientists discovered new cells in human lungs to maintain a healthy respiratory system – Photo: SHUTTER STOCK

The new cells are called respiratory recirculating filter (RAS) cells. They are found in small, branching passages called bronchioles and are covered by alveoli – air sacs devoted to the exchange of oxygen and carbon dioxide with the blood.

The new RAS cells are similar to stem cells, which can differentiate into any other cell type in the body. They also have the ability to repair damaged alveolar cells and transform into new cells.

Mr. Edward Morrisey, professor at the Perelman School of Medicine at the University of Pennsylvania (USA) and author of the study, shared with news website Live Science: “Researchers suspect most mammals are likely to have RAS cells in their lungs”.

RAS cells serve two main functions in the lungs. First, they secrete molecules that maintain the fluid lining along the bronchioles, which helps prevent the small airways from collapsing and maximizes lung efficiency.

Second, they can function as type 2 (AT2) alveolar cells, a special type of alveoli that secrete a chemical that is used in part to repair other damaged alveoli.

Professor Morrisey said: “We call RAS cells the precursors of the natural process. They have important functions in maintaining airway health.”

The researchers suggest that RAS cells may play an important role in smoking-related diseases, such as chronic obstructive pulmonary disease (COPD). Every year, more than 3 million people around the world die from COPD, according to the World Health Organization.

In theory, RAS cells would prevent, or at least alleviate, the effects of COPD by repairing damaged alveoli.

However, researchers also suspect that smoking can damage, or even completely destroy, new cells, leading to the onset of diseases like COPD.

COPD patients are often prescribed anti-inflammatory drugs or oxygen therapy to ease their symptoms. However, these are only temporary solutions and cannot reverse lung damage.

RAS cells could be used to improve treatments or even cure COPD, if researchers can properly harness the cells’ regenerative properties.