Dietmar Bast

Diagnosing wheat allergy remains challenging due to the use of oral wheat provocations, which implicate risks to patients and highlights the need for safer, non-invasive diagnostic methods. Here, we present the first direct comparison of a pediatric and adult cohort to study wheat allergy and wheat tolerance using an improved and validated basophil activation test (BAT). Blood samples from 24 children and 26 adults, clinically classified as facing oral food challenges, were analyzed using our bin-based BAT, enabling standardized data analysis and visualization. In children, the BAT showed significantly higher median basophil activation in wheat-allergic compared to wheat-tolerant individuals. Receiver operating characteristic analysis revealed that BAT responses to wheat, gluten, and gliadin extracts (area under the curve (AUC): 0.71–0.73) had greater diagnostic accuracies than extract-based wheat and gluten-specific immunoglobulin E (sIgE) measurements (AUC: 0.69, 0.70). However, Tri a 19-sIgE, showed the highest diagnostic performance (AUC: 0.97). In adults, BAT responses did not differ significantly between allergic and tolerant individuals. The bin-based BAT is a robust and reproducible diagnostic tool for wheat allergy diagnosis with automated data analysis capabilities. Significant differences were only evident in the pediatric cohort, indicating age-related immunological differences in basophil responsiveness or immune sensitization profiles. These differences could be linked to immune system maturation, variations in immunoglobulin E (IgE) avidity, or differential expression of the high-affinity IgE receptor (FcεRI) on basophils. While Tri a 19 sIgE was the best single predictor in children, its clinical utility remains controversial due to conflicting results in the scientific literature.