Research conducted by a University of Cambridge team expands the possibility of creating preventative medicines

Scientists have discovered the trigger for allergic reactions to cats, paving the way for developing preventative treatments.

A team at the University of Cambridge looked at the immune system's extreme reaction to cat allergens and discovered that the most common cause of severe allergic reactions are because of the Fel d 1 protein found in particles of cat skin, know as cat dander.

In a study published in the Journal of Immunology, researchers found that cat allergens activate a pathway in the body when in the presence of a common environmental bacterial toxin know as LPS.

Now, new treatments could be developed that attempt to block this pathway and inhibit allergic reactions.

Allergic reactions occur when the immune system overreacts to a perceived danger. Instead of identifying and responding to a harmful virus or bacteria, it misidentifies different allergens, including dander, as dangerous and mounts an immune response which triggers sneezing, coughing and wheezing.

Researchers exposed human cells to cat and dog dander proteins in the presence or absence of low levels of LPS. The researchers found that when LPS is present, it increases the signalling to the body’s immune system, intensifying the body’s inflammatory response to the cat protein.

Dr Claire Bryant, lead author of the research from the University of Cambridge's Department of Veterinary Medicine said the team are hopeful that this study will lead to new and improved treatments for cat and dog allergy sufferers.

“How cat dander causes such a severe allergic reaction in some people has long been a mystery. 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.”

“As drugs have already been developed to inhibit the receptor TLR4, we are hopeful that our research will lead to new and improved treatments.”

Researchers also believe that dog-allergy suffers could also benefit from treatments designed to inhibit TL4.