Lungs' Hidden Cells May Hold the Key to Stopping Allergies for Good

A new study has uncovered how the lungs store long-term protection against allergies. The breakthrough reveals that structural cells—not immune cells—hold the key to blocking allergic reactions. This discovery could lead to better ways of preventing respiratory allergies, which have surged in recent years.

Researchers at France's Pasteur Institute found that fibroblasts, a type of connective tissue cell in the lungs, play a vital role in preventing allergies. These cells undergo epigenetic changes after exposure to microbial fragments, creating a lasting defence against allergic triggers.

In experiments, mice given microbial fragments before allergen exposure remained protected for at least six weeks. Some even stayed shielded for over three months. Without this initial exposure, the same mice developed severe lung hypersensitivity and worsening reactions upon re-exposure.

The findings challenge the long-held belief that only immune cells store immunological memory. Instead, the study shows that structural cells in the lungs retain this protective memory, blocking allergic responses for extended periods.

This research comes as respiratory allergies, such as allergic rhinitis and asthma, have risen sharply. Over the past decade, cases have jumped by 20–50% in countries like the US, UK, Australia, and China. Urbanisation, pollution, and climate change are driving the increase, according to WHO reports and studies in The Lancet.

The discovery opens new clinical possibilities for preventing respiratory allergies. By targeting lung fibroblasts, future treatments could offer long-lasting protection. This approach may help curb the growing burden of allergies linked to modern environmental factors.