Objective: Recently, oral immunotherapy for food allergy has been successful in NFA using subcutaneous IFN-gamma injection. We are to characterize the clinical findings of NFA and the induction of the oral tolerance to food allergen in NFA after oral immunotherapy using IFN-gamma.
Methods: Non-IgE-mediated food allergies were diagnosed by food challenge, skin prick test and food-specific IgE. Total 77 NFA patients with atopic dermatitis that is characterized by late eczematous skin reaction were selected in this study. 37 subjets were treated with a relevant OIT protocol for NFA. As a control group 10 subjets received only IFN-gamma without allergenic food. 10 subjets receive only food without IFN-gamma, and 20 subjets with NFA did not receive treatment. Patients were evaluated clinically after treatment using subcutaneous IFN-gamma injection.
Results: All patients became successfully tolerized to previously offensive foods (changes in clinical severity scores by food challenge from 15.9 ± 3.6 to 1.8 ± 1.0 points, p <0.001), whereas none of the other controls acquired tolerance. By food challenge, the changes in clinical severity scores were from 17.4 ± 4.4 to 15.5 ± 5.0 points (p >0.05) in a group of only IFN-gamma treatment without food, from 14.6 ± 3.6 to 14.1 ± 3.0 points (p>0.05) in a group of only food challenge without IFN-gamma treatment, and from 15.9 ± 3.7 to 15.4 ± 4.3 points (p >0.05) in a untreated group with neither IFN-gamma nor food.
Conclusions: Non-IgE-mediated food allergy can be successfully treated by relevant oral immunotherapy using IFN-gamma. IFN-gammanseemed to be necessary for the tolerance induction.