In what may be the greatest scientific breakthrough ever for cat lovers with allergies, researchers from the University of Cambridge have finally figured out what causes allergic reactions in people and hope to have a cure on the market soon.
It’s long been known that the cat protein Fel d 1, which is secreted through their skin and saliva and ends up on dander, is what causes the symptoms of an allergic reaction, such as itching, sneezing, rashes or asthma attacks in allergy sufferers. But how exactly it triggers an allergic response in people hasn’t been understood until now.
According to a press release, the researchers discovered that when dander is released in the presence of a common environmental bacterial toxin called lipopolysaccharides, or LPS, it activates an immune receptor in people called TLR 4, which recognizes the protein contaminated with the toxin. It then triggers a reaction, which is what causes the inflammatory response.
“How cat dander causes such a severe allergic reaction in some people has long been a mystery” said Dr. Clare Bryant, lead author of the study, which will be published in the Journal of Immunology. “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 recognises it, the receptor TLR4.”
To figure this out, researchers exposed human cells to cat and dog dander proteins with and without low levels of LPS and discovered that when LPS is present, it increases the signals to the body’s immune system, which intensifies the inflammatory response.
When they used a drug to inhibit TLR4, they also found that doing so blocked the effects of cat dander on cells and stopped the inflammatory response from ever happening.
Armed with this knowledge, scientists now hope to develop drugs that stop the allergic reaction, instead of trying to treat the symptoms. Currently, allergy sufferers have to rely on antihistamines, or on building up a tolerance to allergens.
There’s good news for dog lovers with allergies too. The researchers also found that the protein in dog dander that causes allergic reactions, Can f 6, also enhances LPS-induced activation of TLR4 and that those who are allergic to dogs may also be able to use drugs that inhibit this receptor.
“As drugs have already been developed to inhibit the receptor TLR4, we are hopeful that our research will lead to new and improved treatments for cat and possibly dog allergy sufferers,” said Bryant.
While there are some cat breeds that are supposedly better than others when it comes to triggering allergic reactions, there are no guarantees that a person won’t have an allergic reaction. For those who have been willing to spend big bucks on such pets who are marketed as hypoallergenic, a cure for allergies may also be good news.
Just last week, Allerca: Lifestyle Pets, which claimed to have made the world’s first proven hypoallergenic cat in 2006 (complete with price tags up to $28,000) was called out on its claim by both experts and customers for selling cats that were no more hypoallergenic than “regular” cats.
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