D1.279 - Oral Immune Tolerance Induction Therapy with IFN-gamma in children with rice allergy

Food allergy (FA) is an immune system reaction with two mechanisms: IgE-mediated and non-IgE-mediated. Clinically, oral immunotherapy for FA has been tried to induce oral tolerance to food allergens. Rice allergy is generally low but varies significantly by region, with higher rates in East Asia, where rice is a staple food. Rice allergy is more often reported in adults than in children in some regions, though pediatric cases are also observed, particularly in infants with atopic dermatitis (AD). Moreover, rice allergen-induced AD was found to be one of the symptoms of a non-IgE-mediated and delayed type of IgE-mediated allergic reaction. IFN-γ has been used to induce tolerance to FA as an immunomodulatory biologic. Recently, oral tolerance induction has been successfully achieved using subcutaneous interferon gamma (IFN-γ) injection (3x10⁶ IU/m²) in patients with rice-induced AD. We are to characterize the clinical findings of rice allergy and oral immunotherapy using IFN-γ injection.

This retrospective study analyzed data from 17 patients with rice allergen-induced FA who received IFN-γ injections over a 20-year period at Chungnam National University. The study aimed to evaluate the clinical outcomes of oral immunotherapy combined with IFN-γ treatment.

17 patients with rice allergen-induced FA became successfully tolerant to rice after oral immunotherapy for. The male-to-female ratio was 9:8. The average age was 7.01 years. Rice-specific IgE was positive in 7 subjects (IgE-mediated), but the other 10 subjects had negative specific IgE (non-IgE mediated). There was no difference between IgE-mediated and non-IgE-mediated rice allergy in age, gender, and eosinophils (P>0.05), but differences in the level of IgE (769.6 ± 591.6 vs 132.9 ± 134.6, P=0.004). The duration of oral tolerance induction was 16.5 ± 6.9 weeks. After IFN-γ injection, the threshold of rice allergen was 8.6 ± 12.1g in the oral food challenge test.

Rice-induced FA can be successfully treated by relevant oral immunotherapy using IFN-γ injection. IFN-γ injection would be necessary for the tolerance induction in rice-induced FA.