A MUCH-loved animal synonymous with Scotland may hold the key to preventing people developing allergies from a not so much-loved native.

 

Scientists believe the Shetland pony, a long-time favourite of children across the country, could help to bring an end to the misery of itching and redness caused by pesky midge.

According to researchers at Edinburgh University, it is all down to the way the ponies' immune system reacts to bites.

Their immune system prevents allergic reactions when they are bitten, rather than triggering them, and scientists believe this could help to find a way to stop people suffering from allergies.

It was previously thought that ponies which did not suffer an allergic reaction to bites did so because their immune systems did not recognise allergens carried by the insects, and as a result did not respond.

However, the team at Edinburgh has now shown for the first time that all horses respond and that their immune system can act in two different ways to the irritants in midge bites.

The ponies' immune systems either produce allergy symptoms - such as itching and inflammation - or prevent them.

Researchers believe that they may be able to prime the human immune system to do the same - bringing an end to the seemingly endless scratching the bites can provoke.

Dr Dietmar Zaiss, of Edinburgh University School of Biological Sciences, who led the study, claimed the discovery was significant.

He said: "To our knowledge, this is the very first study of a natural allergic disease in which we can show that immune responses to allergens can take two directions, either leading to allergy or to tolerance.

"We believe this finding could have direct practical implications, for example by helping immune responses to choose the 'right' direction in individuals who we would like to protect from developing occupation-associated allergies."

The study, carried out in collaboration with researchers in the Netherlands and published in the journal PLOS ONE, found that the horse immune system can release various types of factors - known as cytokines - which affect the behaviour of other cells.

Ponies that react to midge bites release cytokines - known as IL-4 - which trigger allergy symptoms.

While animals not displaying symptoms release another cytokine - INF - which blocks different immune cells that would otherwise trigger allergic reactions.

The response is similar to what happens in humans with allergies and researchers believe understanding what triggers the different reactions could hold the key to stopping people developing itching and redness.

Those who suffer a reaction to bites from midges and gnats develop small lumps on their skin which are usually very itchy and in some extreme cases sufferers can develop fluid-filled blisters and weals.

Allergies in humans are caused by a complex interaction between genetic and environmental factors and researchers say the reason why some people develop a reaction, while others do not, is not fully understood.

The team says it is unclear what causes the immune system to activate an allergic response over a protective one, but is hoped that further studies using the ponies may help to reveal the answer and put an end to the misery caused to millions every year.

The research was funded by the Dutch Foundation for Technical Sciences (STW).