KANSAS CITY — Research projects in Manhattan, Kas., and Madrid, Spain, are tackling the same issue, one that might give hope to millions of people who want to eat wheat but can’t. The researchers are examining reactive proteins in wheat varieties, seeking to one day develop varieties that may be incorporated into flour and food that is safe for people with celiac disease to eat.
It could take years.
While hundreds of proteins come together to make up wheat gluten, only a few have the reactive properties that inflict people with celiac disease, said Chris Miller, Ph.D., director of wheat quality research at Manhattan-based Heartland Plant Innovations, which is trying to identify the reactive proteins.
Research at the Technical University of Madrid involves similar work, which was featured in the Dec. 15, 2016, issue of Food Chemistry.
In the United States, about 1% of the U.S. population has celiac disease, according to Beyond Celiac, Ambler, Pa., an organization that seeks to advance understanding of celiac disease and works to secure early diagnosis and effective management. People with celiac disease must follow a gluten-free diet, which means they must avoid wheat as well as barley, rye and triticale.
|Chris Miller, Ph.D., director of wheat quality research at Heartland Plant Innovations|
“Avoiding wheat in your diet is incredibly difficult,” Dr. Miller said. “There are just so many foods that contain wheat.”
Gluten is more of a baking term than a scientific term, he said.
“Gluten is really a loose, non-scientific term to define maybe hundreds of wheat endosperm proteins,” Dr. Miller said. “Whenever you add water to flour, you form a dough. That hydrated protein mass that holds the dough together is what we call gluten.”
Researchers at Heartland Plant Innovations are studying modern-day wheat varieties as well as the older wild varieties that are relatives, or parents, of current wheat varieties.
“When the project started, it really was focused on identifying the reactivity of wheat — so, what proteins in wheat cause celiac disease reactivity,” Dr. Miller said. “But then when we got into it, we realized that there are other important end product uses of wheat, not just related to celiac.”
Baking characteristics such as volume loaf might be improved through studying the storage proteins in wheat, he said.
“It’s going to take years before we develop a wheat variety that is a celiac-safe wheat variety, but that’s our goal,” Dr. Miller said.
Heartland Plant Innovations, a private company, receives funding from the Kansas Wheat Commission, Manhattan. More funding from more funding partners may speed up the process, he said.
“Our biggest barrier right now is we really need a medical research partner,” he said. “At some point you have to test human reactivity.”
According to the researchers in Madrid, varieties of wheat have been shown to present toxicity through some components of gluten called epitopes that are responsible for the autoimmune response in celiac patients.
The published study in Food Chemistry investigated the hypothesis that modern wheat breeding practices may have contributed to the increase in celiac disease prevalence during the latter half of the last century. The study’s results did not support the hypothesis as Triticum aestivum spp. vulgare landraces, which were not subjected to breeding practices, presented higher amounts of immune-stimulatory epitopes when compared to modern varieties.
The researchers in Spain analyzed various kinds of wheat from several countries, all produced in the 2013-14 agronomic year at the Experimental Station at the Agronomic, Food and Biosystems School of Madrid. They focused on gliadins.
The scientists assessed the presence of T-lymphocytes, a type of cell in the immune system, related to celiac disease in various kinds of wheat. The results showed different varieties of wheat produce different immune response depending on the T-lymphocytes cells analyzed, Ms. Rodriguez-Quijano said.“Out of the proteins in gluten, gliadins have the greatest clinical effect against the innate and adaptive immune responses that lead to (celiac disease),” said Marta Rodriguez Quijano Urquiaga, a researcher at the Technical University of Madrid.
“Genetic diversity makes it difficult to obtain a variety of wheat with no toxicity while maintaining the viscoelastic properties of gluten,” she said. “For this reason, learning about the different varieties would enable production techniques to be developed to achieve this.”
Identifying the quantity and distribution of toxic epitopes is crucial in celiac disease.
“We hope this study enables products to be developed that are safe for celiacs with detoxification processes that combat the poor nutritional and technological characteristics of gluten-free products and thereby contribute to improving patients’ quality of life,” Ms. Rodriguez Quijano Urquiaga said.