Researchers have identified a protein that they say could be responsible for triggering food allergy in humans and would be useful in developing more accurate tests for such allergies.
Researchers led by M. Cecilia Berin at Mount Sinai School of Medicine, New York, showed for the first time that CD23, a protein normally present in a person's intestinal tract, acts as a receptor for IgE, a protein associated with allergic reactions.
The researchers studied nine paediatric patients aged three to 17 years. They believe that the presence of CD23 may provide a surrogate method of looking at the gut without invasive tests like biopsies, reported the science portal EurekAlert.
Food allergies are an exaggerated immune response in which the body produces histamines and antibodies that induce symptoms in the gastrointestinal tract, airways and skin, and in the most severe cases induces anaphylactic shock, an often fatal systemic reaction.
These allergies are often characterised by abdominal pain, diarrhoea, vomiting, hives, swelling of the eyelids, face, lips and tongue, shortness of breath or wheezing and difficulty swallowing, among other symptoms.
The most common allergens are peanuts, tree nuts, shellfish, fish, wheat, milk, eggs and soy.
Food allergies often present a unique problem for allergy testing since not every patient has detectable levels of immunoglobulin E (IgE) in their serum, especially patients with delayed allergies.
A number of reliable testing methods exist for food and other allergies, including skin tests and serum IgE tests; however, they may not accurately diagnose the allergies.
The researchers said that CD23 can be detectable in stool samples from food allergic patients. They are now intending to conduct larger scale trials to determine how CD23 in the stool correlates with clinical findings.
"We hope to determine that CD23 offers a promising target for food allergies that leads to more accurate, easier to tolerate tests for these patients," Berin said.