Note: Single-source report; awaiting corroboration.
Scientists investigating why the immune system reacts to harmless foods have identified specific sensors in intestinal immune cells that recognize parts of dietary proteins. In a mouse study, researchers found seven distinct sensors in specialized gut immune cells that responded to proteins in the animals' chow.
Of these sensors, five were activated by corn protein, one by wheat protein, and one by soybean protein. These sensors targeted specific portions called epitopes, with the most common epitope found on a corn protein. Specialized cells recognizing this corn protein appeared in mice at about four weeks old, coinciding with their first exposure to the food. These cells communicated with other immune cells to prevent an immune attack on the food protein, suggesting a mechanism for tolerance formation.
Dr. Elizabeth Sattely of Stanford University, a co-leader of the study, stated that tolerance to food is not simply a lack of immune response but an active and adaptive process. Certain intestinal cells continuously monitor dietary intake, specifically seeking proteins and signaling to the immune system when foods are safe, according to the study.