Is the Quantification of Antigen-Specific Basophil Activation a Useful Tool for Monitoring Oral Tolerance Induction in Children With Egg Allergy?

OBJECTIVES To assess modifications in baseline specific IgE- and anti-IgE- and antigen-specific-mediated basophil activation in egg-allergic children. The values were compared before and after the children completed specific oral tolerance induction (SOTI) with egg. PATIENTS AND METHODS We studied 28 egg-allergic children who completed SOTI with egg. The basophil activation test and specific IgE determinations with egg white, ovalbumin, and ovomucoid were performed in all 28 children. RESULTS A decrease in antigen-specific activation with egg white, ovalbumin, and ovomucoid was observed only at the 2 lowest concentrations used (5 and 0.05 ng/mL). Baseline activation was higher in patients with multiple food allergies and in those who developed anaphylaxis during SOTI; this activation decreased in both groups after completion of SOTI. A significant decrease was also observed in specific IgE values for egg white, ovalbumin, and ovomucoid after tolerance induction. CONCLUSIONS Food tolerance induction is a specific process for each food that can be mediated by immunologic changes such as a decrease in specific IgE values and in specific and spontaneous basophil activation.