Comparison of dominant foodborne and inhalant allergies developing in the first 5 years of life

Background: During the first 5 years of life, atopic individuals may develop cutaneous or respiratory symptoms with foodborne or airborne allergens. The route and dose of exposure are associated with sensitization. However, limited studies compare food and airborne allergies in these children. Objective: To characterize and compare the developmental patterns of symptoms, specific IgE (sIgE)/specific IgG4 (sIgG4), and B cell subsets in response to food or airborne allergens under 5 years old. Methods: Children aged from birth to 5 years old with food allergy and/or respiratory allergy symptoms were recruited from Jan 2019 to Dec 2021. Clinical parameters were systematically documented, and the sIgE responses to 29 common allergens were quantified via ImmunoCAP. A subset of participants (n = 45, with 9 cases in each age group) underwent assessments of sIgE/sIgG4 to egg, milk, and house dust mite (HDM) components. Peripheral B cell subsets were phenotypically characterized using multiparametric flow cytometry (n = 20). Results: ) highly expressed in food allergies. Conclusions: Our study demonstrates the frequency, route, and dosage of exposure may contribute to distinct variations in the repertoire of allergen-specific IgE/IgG antibodies and B cell subsets, highlighting the importance of exposure modalities in shaping early immune responses.