Researchers have identified one of the proteins that may be responsible for causing food allergies, which could lead to the development of more accurate non-invasive tests to identify true food allergies, according to a study published in the July issue of Gastroenterology, the journal for the members of the American Gastroenterological Association.
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 food allergies. The oral food challenge is considered the most accurate test for food allergies but is expensive to administer and has to be done in a controlled environment. Immunoglobulin (antibody) E is a protein produced by plasma cells (or B-Cells , a type of lymphocyte ), which is designed to control the immune response in extracellular fluids by binding to substances in the body that are recognized as foreign.
The study, conducted at the Mount Sinai School of Medicine, New York, showed for the first time that CD23, a protein normally expressed in a person's intestinal tract, acts as a receptor for IgE, a protein associated with allergic reactions, and enables it to participate in food-allergic reactions.
"We believe that the presence of CD23 may provide a surrogate method of looking at the gut without invasive tests like biopsies," according to M. Cecilia Berin, PhD, assistant professor, pediatrics/allergy and immunology, Mount Sinai and lead author of the study.
Results of this study showed that CD23 was detectable in stool samples from food allergic patients, but not the controls, suggesting either increased levels of CD23 on intestinal cells or an allergen-induced shedding of CD23 in food allergic patients. Additionally, researchers found a strong correlation between the level of CD23 and food-specific IgE in the stool, demonstrated by the availability of IgE antibodies to interact with CD23 on the outside surface of the gastrointestinal wall.
Researchers collected stool samples from nine pediatric patients (age range three to 17 years) who underwent an oral food challenge, during which they were administered either egg or milk in a controlled environment. All patients had a history of allergies to these foods and had reacted positively through other testing methods. Their symptoms, which occurred less than two hours after the food challenge, included skin reactions, breathing problems and gastrointestinal problems or a combination. They were matched to five pediatric controls with no food allergies.
"Based on the results of our study, we intend to conduct larger scale trials of patients with food allergic disorder to determine how CD23 in the stool correlates with clinical findings," according to Dr. Berin. "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."
Food allergies affect an estimated six to eight percent of American children age four years or younger and approximately two percent of adults, according to the National Institute of Allergy and Infectious Diseases (NIAID). The study authors estimate that three and a half to four percent of these food allergies are IgE-mediated. While many people believe they have food allergies, the majority of individuals experience food intolerance.
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 characterized by abdominal pain, diarrhea, 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.
Aimee Frank | EurekAlert!
Electrical 'switch' in brain's capillary network monitors activity and controls blood flow
27.03.2017 | Larner College of Medicine at the University of Vermont
Laser activated gold pyramids could deliver drugs, DNA into cells without harm
24.03.2017 | Harvard John A. Paulson School of Engineering and Applied Sciences
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
27.03.2017 | Earth Sciences
27.03.2017 | Life Sciences
27.03.2017 | Life Sciences