A team of researchers from Hiroshima University, Aichi Children's Health and Medical Center, and Shimane University in Japan announced on July 15 the development of a new diagnostic blood test that improves the accuracy of food allergy detection.
Current diagnostic blood tests often fall short in determining which substances patients should avoid to prevent allergic reactions. Allergies are caused by an overreaction of the immune system to harmless substances such as food, pollen, or dust mites. The severity of allergic reactions can range from mild symptoms like itchy skin or watery eyes to life-threatening anaphylactic shock. Accurate identification of allergens is crucial for individuals with severe allergies.
Healthcare providers typically use tests that measure which allergens a patient's IgE antibodies react to; however, these tests do not always establish whether these antibodies are responsible for producing symptoms. To address this gap, the research group developed a new allergen-specific IgE test based on the existing AlphaCL method. This modified method assesses whether a patient's IgE antibodies can trigger an immune response without requiring viable cells or specialized techniques.
Koga said, "[Our modified] AlphaCL method allows assessment of allergen-induced FcεRI cross-linking without the use of cells. In other words, it enables evaluation not only of how much IgE is present but also of how much functionally active IgE capable of inducing allergic reactions is present, using a simple and reproducible system. This study demonstrates the feasibility of detecting functional, [allergy-inducing] IgE through a more practical and accessible approach, highlighting the methodological significance of this technique." The improved AlphaCL method uses modified allergens to remove interfering serum components before detection and was shown to maintain substantially stronger signal responses compared with conventional methods.
The researchers tested their improved method using patient sera with allergies to common foods such as egg, wheat, and milk. The new assay detected allergen-sIgE in 93.3% (28 out of 30) patients who had positive oral food challenge results—a gold standard for diagnosis—suggesting broad applicability across different allergens.
Koga said, "We seek to clarify the fundamental differences between assays that measure the quantity of IgE antibodies and those that assess functional IgE activity. Ultimately, our goal is to establish a new framework for evaluating food allergies by integrating both the quantity and the function of IgE antibodies, thereby enabling a more accurate and comprehensive assessment of clinical reactivity." Other contributors included Tomoharu Yokooji, Rina Aikawa and Ryohei Ogino from Hiroshima University; Teruaki Matsui and Komei Ito from Aichi Children's Health and Medical Center; Yuko Chinuki and Eishin Morita from Shimane University; Takanori Taogoshi and Hiroaki Matsuo from Hiroshima University Hospital.
