Immune inequity in gut may trigger celiac disease

Blocking this compound in mice helped overturn the disease, U.S. researchers said on Wednesday. Vitamin A and retinoic acid, a byproduct of vitamin A used in the acne treatment Retin-A and Roche's former acne drug Accutane, may intensify the problem, acting as a trigger for the inflammatory response, the team said. The findings, published in the journal Nature, propose that an imbalance of compounds like Interleukin 15 that control the immune system could be an underlying cause of food allergies.

"If there is a disregulation in the intestinal environment, this alone can explicate how you can lose tolerance to some food items," Dr. Bana Jabri of the Digestive Disease Research Core Center at the University of Chicago, who led the study, said in a telephone meeting. "It is a first time a pathway has been recognized," she added. Celiac disease is caused by an abnormal immune reaction to gluten, a protein found in wheat, rye, barley and other foods. It happen in about 1 percent of the population, and can lead to harsh health problems including anemia, poor bone health, fatigue and weight loss.

To study it, the team first had to reconstruct the disease in mice. They knew that many people with celiac disease had high levels of Interleukin-15 in their intestines. When they enlarged levels of this immune system compound in mice, they developed all the early on symptoms of celiac disease. Adding retinoic acid to the combine only made the symptoms worse, reason inflammation and tissue damage. When they blocked IL-15, however, the sick mice reverted to usual and were once again able to tolerate gluten.