The identification of key molecules that make gluten toxic could one day help those with coeliac disease.

People with coeliac disease must currently avoid eating gluten found in most breads, cereals, pasta, biscuits, beer and many other foods.

This is because gluten protein in grains such as wheat, barley and rye sets off an allergic reaction in people with coeliac disease, causing their immune system to damage their small intestine.

Ever since gluten was discovered as the dietary trigger for coeliac disease 60 years ago, scientists have been trying to identify which part of the protein is the culprit.

Scientists had identified one peptide in wheat gluten as a problem but now  have revealed a much more complete picture of what can trigger the autoimmune response.

 

Immune response studies

Nine years ago researchers  began looking at the immune response activated in people fed wheat, barley or rye.

By comparing the type of T-cells found in the patients’ blood with a “library” of 16,000 gluten fragments, it was discovered which fragments triggered the biggest immune response.

To their surprise, the researchers found that the peptide known to be toxic in wheat gluten was not a problem in the patients fed barley and rye.

Instead, the researchers found each of the three grains had their own toxic peptide that triggered an immune response.

They also found one peptide, dubbed the “universal toxic peptide”, was a problem no matter what grain was eaten.

“Three out of four critical peptides for coeliac disease are now revealed in this study. So it changes the way that we understand coeliac disease.”

Immunotherapy

The findings are being used to develop a new class of drugs, called peptide-based immunotherapy.

This involves injecting patients with a small amount of the toxic peptides to “desensitise” their body to them.

The researchers say Phase 1 trials of the therapy to assess safety and tolerability were completed in June, and final results are expected in coming months.

The latest findings can also be used to develop less invasive diagnostic tests and even help prevent coeliac disease.

If a therapy works, the peptides could even be given to children before they are exposed to gluten to prevent coeliac disease.

 

“The only treatment for coeliac disease at present is a gluten-free diet … The desire for people with coeliac disease is to be able to travel and eat out without any fear as everyone else in the community does.”

“So the promise of other forms of treatment which will enable coeliacs to live, what others would describe as, ‘a normal life’, is obviously enormously appealing.”

It would be a “miracle” if people with coeliac disease could stop worrying about accidently eating gluten.

“That could be quite a way off unfortunately, there is still a lot more work to be done.”

It’s advised that people should  stick to a 100% gluten-free diet, including learning how to decipher ingredient lists on labels.

Avoiding trace amounts of gluten is a particular challenge for people eating take-away food or food from restaurants.

It;s easy for gluten-free food to be contaminated with gluten through utensils used to cut bread, serve pasta or through water used to cook noodles, for example.

People with coeliac disease cultivate regular restaurants that understand dietary needs, and have conversations with hosts before attending dinner parties.

Becoming a member of a local coeliac society is useful support for such efforts.

It is estimated that there are 200,000 Australians with coeliac disease and there has been a big increase in the number of people with the condition in recent years.

 

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