A20 was produced when exposed to farm dust.
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The researchers said that the protective effect disappeared after the protein was inactivated in the animals as it left the mucous membrane of the lungs incapable of reducing asthmatic or allergic reactions.
“We already suspect that to some extent, the answer lies in the endotoxines, which form part of the cell wall of specific bacteria”, Hammad said.
Numerous studies have found that children brought up in farms tend to develop resistance to allergies and asthma, as stated in Nature; but just recently, researchers from Vlaams Instituut voor Biotechnologie (VIB) and Ghent University in Belgium discovered that it’s because of farm dust. The enzyme keeps the immune system from overreacting to common allergens, such as house dust mites, the team found. The researchers think it might lead to a way to vaccinate kids so they’re less likely to develop allergies and asthma. After exposing them, the researchers found that these mice were completely protected against house dust mite allergy, the most common cause of allergies among humans.
With further examination, researchers discovered that a protein called A20 found in lung tissue may have been responsible for the protective response seen in mice exposed to the dust. However, those rodents with mutated A20 were vulnerable to asthma, according the NBC News.
Exposure to farm dust protects the body against harsh reactions to allergens.
Scientists believe that getting exposed to farm dust in early years of growth can help prevent asthma attack.
An enzyme in the epithelial cells called A20 also resulted in dampening the inflammatory responses – something that did not happen in mice that lacked the gene to produce A20.
The Ghent team then tested bronchial cells from healthy people and found that exposure to endotoxins lowers the levels of the same inflammatory molecules studied in the mice.
Until now, Lambrecht says, most explanations for the hygiene hypothesis assumed it acts directly on the immune system’s T cells.
The researchers claim that the A20 exhibits a similar regulatory mechanism in the gut, where the microbiota colony “induces the expression of A20 shortly after birth” helping it to tolerate the beneficial microbes that help in food digestion. But the present study shows that the site of action is in the structural cells of the airways. “Drinking unprocessed milk also seems to ward off asthma in kids, and that effect is unlikely to involve the lung epithelium”, Gary Huffnagle of the University of Michigan, Ann Arbor told Science.
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Finally, it is important to include the opinion of Imperial College London asthma geneticist William Cookson who is not as enthusiastic. Experts said that the study gives a new platform to study hygiene hypothesis.
