A new study published in the Journal of Proteome Research found gluten may be taking too much of the blame for celiac disease, an autoimmune disorder that prevents the small intestine from absorbing essential nutrients.

Gluten, as we’re sure you’ve heard by now, is a protein found in wheat, rye, and barley, and it helps give dough its elasticity. When consumed by someone with celiac, it results in intestinal inflammation and otherwise gastrointestinal problems. But what are the effects of non-gluten proteins? After all, gluten only accounts for around 75 percent of wheat protein.

Researchers and scientists from Columbia University and the U.S. Department of Agriculture decided to investigate the remainder 25 percent of wheat protein in order to see if it does an equal disservice to celiac patients. They screened serum samples from patients with celiac disease and dermatitis herpetiformis (a celiac-related rash) for an immune response to five groups of non-gluten proteins: serpins, purinins, alpha-amylase/protease inhibitors, globulins, and farinins. And compared to healthy controls, researchers wrote celiac patients “exhibited significantly higher levels of antibody reactivity to non-gluten proteins.”

In layman’s terms, non-gluten proteins act as an antigen, which causes the body to produce antibodies against it. As reported by the National Institutes of Health, “antibodies may be produced when the immune system mistakes healthy tissue as a harmful substance, thus causing an autoimmune disorder.”

“The results were surprising to us, because we did not expect to find such a strong antibody response to a specific subset of non-gluten proteins of wheat in celiac disease patients,” Dr. Armin Alaedini, lead study author and assistant professor of medical sciences in the Department of Medicine and the Celiac Disease Center at Columbia University, told Medical Daily in an email. “Historically, all wheat non-gluten proteins have been generally considered to lack toxicity or the ability to trigger an immune response in the context of celiac disease.”

Alaedini added non-gluten proteins would be found in products that contain wheat and related cereals, most of which celiac patients already avoid (as well as those on a gluten-free diet). However, wheat starch may require further investigation as it can have non-gluten protein contamination.

Despite these findings, Alaedini stressed neither he nor his team really knows the pathogenic relevance of the immune response to the identified non-gluten proteins. “It remains to be seen whether these proteins can contribute to inflammatory processes that cause intestinal damage in celiac disease,” he said. “We're continuing this work by looking at the adaptive T cell response, as well as innate immune reactivity, to these proteins in celiac disease patients.

Source: Huebener S, Tanaka CK, Uhde M, Zone J, Vensel W, Kasarda D, et al. Specific Non-Gluten Proteins of Wheat are Novel Target Antigens in Celiac Disease Humoral Response. Journal of Proteome Research. 2014.