Three toxins in food identified as triggers to gluten intolerance: study

By Dr. Ananya Mandal, MDJul 22 2010

Coeliac disease cause by intolerance to gluten present in food and drinks like bread, pasta, cereals, biscuits and beer commonly affects many people all over the world. This affects 1 percent of all people in UK, especially women. Patients are advised to stay away from gluten to prevent damage to their intestines. In spite of this in five years most patients develop problems in their intestines. A gluten free diet is also difficult to maintain. Possible symptoms include diarrhoea, nausea and vomiting, recurrent stomach pain, tiredness, headaches, weight loss and mouth ulcers. These may be mild, moderate or severe in different individuals.

Now the exact mechanism that triggers this immune reaction to certain foods has been uncovered. According to UK and Australian researchers there are three major substances in the gluten found in wheat, rye and barley that can trigger the digestive condition. This discovery may be a stepping stone to development of new therapy or even vaccines for the condition. The findings are published in the journal, Science Translational Medicine.

For the study, researchers studied 200 patients with coeliac disease attending clinics in Oxford and Melbourne. The volunteers were asked to eat bread, rye muffins or boiled barley each with high level of gluten. After six days their blood samples were taken to measure their immune response to thousands of different gluten fragments, or peptides. By comparing the type of T-cells found in the patients' blood with a “library” of 16,000 gluten fragments, the team were able to work out which fragments triggered the biggest immune response. The results showed that some 90 peptides were immunogenic. In other words these 90 could trigger a reaction in susceptible individuals. However three peptides were particularly toxic. They also found one peptide, dubbed the “universal toxic peptide”, was a problem no matter what grain was eaten.

According to Professor Bob Anderson, head of the Walter and Eliza Hall Institute of Medical Research in Melbourne, Australia, “These three components account for the majority of the immune response to gluten that is observed in people with coeliac disease.” “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,” says Professor Anderson.

He explained that based on these findings a potential therapeutic approach using immunotherapy to expose people with coeliac disease to tiny amounts of the three toxic peptides is being developed. Professor Anderson is the CEO, chief scientist, chief medical officer, director and substantial shareholder of Melbourne-based biotech company Nexpep, which is carrying out trials and helped fund the study. In the next few months early results of the trial should be in he said.

According to Sarah Sleet, Chief Executive of the charity Coeliac UK, a vaccine may also be in the horizon. She said, “It's an important piece of the jigsaw but a lot of further work remains so nobody should be expecting a practical solution in their surgery within the next 10 years.”

Funding for the research was received from the National Health and Medical Research Council (NHMRC), Coeliac UK, the Coeliac Research Fund, BTG International and the Victorian Government.