New Approach to Immunotherapy for Severe Peanut and other Food Allergies

Research from North Carolina’s biggest universities that identified new ways to bind polyphenol-rich foods with peanut flour may one day help patients with severe food allergies develop increased tolerance without risking anaphylaxis.

Currently, oral immunotherapy that exposes people with severe allergies to small amounts of peanut flour can still trigger reactions like anaphylaxis when the peanut comes into contact with certain immune cells. Among people who are allergic to peanuts, the surfaces of these immune cells have immunoglobulin E (IgE), which binds to peanut proteins and sets off the allergic reaction.

The possibility of such reactions means that oral therapy can only be given in clinical settings, which makes it expensive. Worse, allergic reactions that take place despite all precautions force many of the most sensitive patients to stop treatment before immunity develops.

But the new study from North Carolina State University, the University of North Carolina and the US Department of Agriculture, published in the Journal of Agricultural and Food Chemistry, indicates that the simple cranberry might be the key to improving immunotherapy and reducing the serious problems associated with allergic reactions.

Food allergies trigger 125,000 emergency room visits and 53,700 episodes of anaphylaxis in the United States each year. Studies have identified nearly 200 foods that can sometimes cause allergic reactions, but the majority of all fatal reactions each year stem from just one food, peanuts.

Prior studies have shown that polyphenols can reduce or eliminate allergic reactions to peanuts and peanut-rich foods because they bind to peanut proteins and prevent those proteins from interacting with IgE inside the body.

But, according to the North Carolina research team, no prior work has found an effective and efficient way to bind polyphenols to peanut protein, a technique that would be suitable for mass production at reasonable prices.

That team began the hunt for such a technique by gathering a wide range of polyphenol-rich foods, everything from berries to tea to cinnamon.

The researchers then liquefied and concentrated each of the foods, used various techniques to mix peanut flour with every candidate and then freeze dried all of the resulting suspensions.

Subsequent analysis showed that concentrated cranberry juice had bound particularly well with the peanut protein, so the study team exposed the cranberry-peanut mixture to cell cultures that had been designed to undergo immune response when exposed to peanut proteins.

There was some response, but it was dramatically lower than the response created by untreated peanut flour.

The researchers then tested the cranberry-peanut mixture in mice that had been sensitized to peanuts and again found a much lower degree of allergic response. Indeed, the cranberry treatment reduced that response by 75% in the mice.

The study’s authors warn that much work remains to be done before their work can help allergy victims who are at risk of anaphylaxis. Still, they think these experiments might prove important.

“Collectively,” they wrote, “these results suggest that the cranberry polyphenol-fortified peanut matrix is hypoallergenic and may have potential to serve as a safer second-generation ingredient for oral immunotherapy trials.”