How to determine which foods are safe and which are not

A study led by scientists at Stanford University (USA) has identified new fragments of food proteins that indicate at intestinal immune cells when to tolerate certain foods. These findings represent a breakthrough in understanding food tolerance and could be useful for Future immunotherapies in people with food allergies.

The researchers—among them Dr. Jamie Blumwho conducted the research at Stanford and recently joined the Salk Instituteand the doctor Elizabeth Sattelyassociate professor at Stanford—found three protein segments called epitopes: one of soyanother of corn and another of wheat. These epitopes interact with regulatory T cellsin charge of determine tolerance or rejection of food, according to Europa Press.

“As a person interested in basic science, I see value in understanding the normal immune process along with the pathology,” Blum explains. Know how the immune system perceives a protein as safe could lead to new therapies that promote tolerance in people with allergies.

Seed epitopes and oral tolerance

Since the 6% of young children and between the 3% and 4% of adults suffer from food allergies, scientists seek to discover what triggers these immune reactions against foods that should be safe. Until now, it is known that specific proteins in the main allergens —like peanuts and eggs— activate mast cells and basophilsfast-acting inflammatory cells.

If we know what causes allergies, why not also understand what causes tolerance? Although the role of regulatory T cells is already understood, It was not known which proteins caused the lack of immune response.

The study, published in Science Immunologystarted with mice fed normal dietwhose regulatory T cells were analyzed to identify recognized food proteins. This is how they found each other three different epitopescoming from corn, wheat and soybeansall of them present in vegetable seed proteinsabundant and commonly tolerated by the immune system.

The T cells reactive to the corn epitope were the most abundant—consistent with the fact that corn rarely causes allergies—while soyone of the main causes of allergy, showed a relevant interaction with the receptor that also reacts to sesameexplaining the cross tolerance between both foods.

The researchers also discovered that the regulatory T cells HE located mainly in the intestine and its activity changes depending on the environment: in the presence of inflammation, they act to attenuate it; In a healthy environment, they help maintain immune balance.

Towards the eradication of food allergies

These seed epitopes represent a new advance in understanding oral tolerance. Regulatory T cells are considered a promising avenue of immunotherapy to treat severe allergies, and could lead to cells are programmed to tolerate certain foods and reduce immune responses to the most common allergens.

“The Diet is our most intimate interaction with the environment —says Blum—. Correctly recognize foods as safe generates an anti-inflammatory environment which favors the absorption of nutrients and prevents allergies. Our research expands knowledge about the main food allergens and make way for therapeutic interventions capable of modifying allergic and autoimmune states”.

In the future, scientists hope apply their methodology in humanssince the reagent developed to track these proteins this available for other laboratories and could speed up the discovery of new clues about oral tolerance mediated by regulatory T cells.