French researchers have discovered that the molecule, known as TL1A, is responsible for the inflammation that causes allergic diseases such as asthma or hay fever.
- French researchers have discovered a new molecule, called TL1A, which is responsible for respiratory allergies.
- It alerts the immune system, along with another molecule called interleukin-33.
- This alert triggers the inflammation that causes allergic diseases.
If you sneeze and have a runny nose whenever pollen is in the air, the culprit could well be the TL1A molecule. French researchers show that the latter participates in the process of inflammation at the origin of allergic respiratory diseases such as asthma (inflammation of the bronchi) and allergic rhinitis (inflammation of the mucous membranes of the nose).
A molecule that alerts the immune system
The work of scientists from Scientific Research National Center (CNRS), the National Institute of Health and Medical Research (Inserm) and Toulouse III University – Paul Sabatier were published in the journal Journal of Experimental Medicine. In it, they show that the TL1A molecule is co-responsible, with another molecule called interleukin-33, for the inflammation that causes allergies.
TL1A is a molecule belonging to the alarmin family. It is therefore what “sounds the alarm” to our body – and more particularly to the immune system – when it is exposed to an allergic substance. This process is quick, just a few minutes after exposure.
But where does TL1A come from? This molecule is emitted by the cells of the pulmonary epithelium, the protective tissue that covers the entire respiratory system, from the pharynx to the lung. But she doesn’t work alone.
A double alarm signal at the origin of allergic inflammation
In their research, the scientists studied lung epithelia from humans and mice. Thus, they observed that TL1A cooperated with interleukin-33, another alarmin molecule, to raise the alarm.
“This double alarm signal will stimulate the activity of immune cells, which will then trigger a cascade of chain reactions responsible for allergic inflammation“, we can read in the communicated from Inserm.
This process of inflammation is at the origin of allergic diseases which affect 17 million people in France, including 4 million asthma patients. According to Inserm, allergic asthma represents approximately 50% of asthma cases. The discovery of the role of the TL1A molecule could allow, in the future, the development of new treatments.
“Alarmins therefore constitute therapeutic targets of major interest for the treatment of allergic respiratory diseases, indicate the authors in the press release. In a few years, treatments based on antibodies blocking alarmin TL1A could benefit patients suffering from severe asthma or other allergic diseases.“
Good news, in particular, for people suffering from allergic rhinitis, for whom this month of April 2024 is difficult. In fact, 75 departments are on red pollen alert according to the National Aerobiological Surveillance Network (RNSA).
