A study has identified how cat dander triggers allergic reactions, and the discovery could lead to new treatments for people with pet allergies.

About 10 percent of Americans have pet allergies, and cat allergies are twice as common as dog ones. But it’s not the animals’ fur that causes the allergic reaction — it’s a protein called Fel d 1 in the cat’s saliva, urine and dander.

Researchers at the University of Cambridge found that when Fel d 1 is exposed to low doses of a common environmental bacterial toxin called LPS, it triggers a pathogen receptor in the body, which causes immune system to respond.

Allergic reactions are simply the result of the immune system overreacting to a perceived threat. In the case of cat allergies, the body’s immune system may respond to Fel d 1 with sneezing and wheezing.

"How cat dander causes such a severe allergic reaction in some people has long been a mystery,” said lead study author Dr. Clare Bryant in a news release. “Not only did we find out that LPS exacerbates the immune response's reaction to cat dander, we identified the part of immune system that recognizes it."

Scientists also found that Can f 6, a protein found in dog dander, triggers the same immune reaction as feline dander.

With this new knowledge of how these proteins trigger allergic reactions, new treatments could be developed for allergy sufferers that aim to eliminate the reaction instead of simply treating its symptoms.

Drugs to inhibit the process are already under development, and researchers told The Daily Mail that a pill or inhaler could be on the market within five years.

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