Scientists announced an interesting link between a common virus and celiac disease, one of the pernicious gastrointestinal conditions brought on by the presence of gluten in foods. This is not the first time the blame has been shifted to a virus, but the new research provides more compelling evidence for the involvement of a virus in celiac.
Celiac disease is quite common in the population, affecting about 1 percent of people, or 1 in 133 Americans. The condition is an autoimmune disorder triggered by gluten, a protein found in common foods like bread and pastas. Unlike a food allergy, gluten causes several autoantibodies to be produced, which go on to wreak havoc in many organs. Notably, villi – finger-like projections that line the intestines – are most vulnerable to attack. This leads to the classic celiac symptoms, which include diarrhea, abdominal distension, and other ailments associated with malabsorption of nutrients.
Currently, there is no cure for celiac disease. The only effective treatment for the condition remains a diet completely devoid of gluten.
The search for a celiac cure has been complicated by the mysteries surrounding the etiology of the disease. While scientists have established some genetic predisposition to the disease, not everyone who has the disease carry the mutation, and not everyone who has the mutation carry the disease. For example, the genetic variants associated with celiac are found in about 30 percent of Americans. Yet, only about one percent of Americans are affected.
The evidence points to other factors, exposures, or triggers. Viral infection has been put forth as a contender for celiac trigger. To test this hypothesis, scientists from the University of Pittsburgh focused on a common virus known as the reovirus, which affects many children but is considered totally benign.
Led by Dr. Terrance Dermody, the team observed that people with celiac seemed to have higher levels of antibody for the reovirus. "It's a clue that people who have celiac may have been exposed to reovirus before the development of their disease," said Dermody.
They then investigated two strains of the virus in mice, and found that one strain seemed to elicit an intestinal immune response in the presence of gluten. The mice developed "an immunological response against gluten that mimics the features of humans with celiac disease," said Dr. Dermody.
Based on their observations, the team hypothesized that presence of the virus in association with gluten can cause the body to mistaken gluten as the invading pathogen. "It's all about the timing," said Dermody.
While the results can’t place the blame squarely on reoviruses, it suggests there is a strong link between the virus and the disease. “[Celiac disease] is a complex disorder that likely requires several environmental perturbations to permanently disrupt tolerance to gluten, the authors wrote. Yet, if further research can pinpoint the virus as a cause of celiac, it would open the possibility of vaccination as a cure for the disease.
Additional sources: EurekAlert, NPR, Popular Science