A team of scientists announced that they have identified a new type of cell developing in the human lung. These cells play a vital role in the proper functioning of the respiratory system. They may also inspire new treatments to combat the effects of some smoking-related diseases.
Human lungs are significantly different from the lungs of mice. In humans, the distal branches of the airways intertwine with the alveolar gas exchange niche to form an anatomical structure known as the respiratory bronchioles. Lacking these structures, mice retain the cellular and molecular mechanisms that control respiratory bronchioles in human lungs. still misunderstood.
Until now, laboratory research has still relied on mouse models for its experiments and analyses, which has caused some frustration for scientists who are aware of these different lung architectures.
In a recent study, a team led by Edward Morrissey at the University of Pennsylvania has finally used new technology to take lung tissue samples from healthy human donors and analyze genes in individual cells.
Analysis of these tissues eventually revealed the presence of a new cell type called airway secretory cells (RAS) found in bronchioles. Details of this work were published in the journal Nature.
Two main roles
According to the study, these cells perform two main functions. First, they release molecules capable of maintain mucus lining the bronchioles, thereby increasing the efficiency of the lungs. On the other hand, these cells appear to serve precursor cells. We remind you that a progenitor cell is a cell capable of differentiating into another type of cell in the same way as stem cells. Here, RAS cells could differentiate into alveolar cells type 2 (AT2). These are a special type of alveoli that release a chemical that is partly used to repair other damaged alveoli.
In their study, the researchers also note that if these cells are absent in mice, then, on the other hand, they present in ferrets, whose respiratory system is more like a human. As a result, they suggest that most mammals of the same or larger size are likely to develop them as well.
A possible path to new treatments?
The discovery of these new cells could make it possible to fight some respiratory diseases such as chronic obstructive pulmonary disease (COPD). This disease is characterized by progressive degeneration of lung tissue and partially reversible airway obstruction. As a result, the lungs struggle to absorb enough oxygen. The disease can also lead to emphysema. There are several risk factors such as smoking, childhood breathing problems, or air pollution.
Theoretically, RAS cells should prevent the consequences of COPD by repairing damaged alveoli. However, researchers suspect that certain factors, in particular smokingmay damage them. Thus, we might ask ourselves if introducing new RAS cells could help improve treatment or even cure the disease. This hypothesis, of course, should be the subject of further research.