According to recent findings, people who grow up on dairy farms suffer from fewer asthma attacks and allergies.
The study was conducted by Ghent University in Belgium, and it showed that upon contact with farm dust, the body releases a protein called A20, leading allergens to have lower impact on the respiratory tract.
It had long been suspected that farm life could be beneficial for warding off allergies. For instance, previous research had shown that only a quarter of Swiss children living on farms suffered from allergies, compared to 45% of those in the general population.
In this new experiment, scientists exposed mice to farm dust extract, from Germany and Switzerland.
It was discovered that following this exposure the mice were completely unaffected by the dust mite allergy, which is the most commonly encountered allergy among humans. Its main symptoms are sneezing and runny nose, but signs of asthma such as wheezing and labored breathing are also frequent.
Farm dust had caused mice to produce the A20 protein, which had a protective effect on them. As soon as the enzyme was removed from their lungs, the mucous membranes could no longer fight the allergens.
Researchers proceeded by studying 2,000 human subjects who grew up on farms, and revealed that the majority of them had no allergies or asthma. The few who exhibited such symptoms had a malfunctioning A20 protein, due to genetic factors.
In the past, the A20 enzyme has been proven to control inflammation and to allow newborn babies not to overreact to benign bacteria as they leave the birth canal.
“At this point, we have revealed an actual link between farm dust and protection against asthma and allergies”, explained Bart Lambrecht, professor of pulmonary medicine at Ghent University.
This research may remind some of the hygiene hypothesis, which claims that children are more likely to develop respiratory issues such as allergies and asthma due to lack of exposure to dirt and friendly microbes.
Endotoxin, which is widespread in farm environments, may help regulate an overactive immune system, causing fewer harmful reactions, but it has to be used in conjunction with the A20 enzyme.
According to William Parker of Duke University Medical Center, lack of exposure to intestinal worms and other parasites may also lead to “the over-inflammatory state of Western immune systems”.
The findings were published in the “Science” journal and they may play an instrumental role in developing an anti-asthma vaccine and new therapies in the future.
Nowadays, 50 million Americans suffer from seasonal allergies and a cure is long overdue. However, several more years of research will be needed before such treatments become available to patients.
Image Source: Dennis Mojado