Study explores why exposure to dust protects us from allergies

The results of a new study appear to explain why growing up on a dairy farm could protect children from developing asthma and allergies.

Children who grow up on dairy farms rarely develop asthma or allergies and it is thought that this is due to their exposure to particles in the air around manure and animal feed which can trigger mild inflammation in the airways.

In a new study, published in the journal, Science, researchers aimed to shed light on this process to understand how this protects the body’s immune system from allergens.

The researchers exposed mice to farm dust over a period of two weeks. The same mice were then exposed to dust mites to see how their body reacted to the allergen. The researchers found that the cells lining the lungs produced lower levels of immune cells compared with mice that had not been exposed to farm dust.

The scientists identified a potential link between this inflammatory response and a specific substance in the body that increases the rate of chemical reactions, known as the A20 enzyme.

They found that mice engineered not to produce this substance gained no protection from early exposure to farm dust. In addition, when 500 children from farms were tested, the researchers noted that those who produced less of the substance, due to their own individual genetic characteristics, were five-times more likely to develop asthma.

The results suggest that boosting the activity of the A20 enzyme could help to protect children from developing the disease. However, the researchers still have a number of questions to answer, and further studies are needed.                                                                                                          

Read the original journal article.

Find out more about the Healthy Lungs for Life campaign, which is raising awareness of the importance of clean air.