Egg Yolk Provides Th2 Adjuvant Stimuli and Promotes Sensitization to Egg White Allergens in BALB/c Mice

• Published in: Molecular nutrition & food research 2018-07, Vol.62 (13), p.e1800057-n/a
• Main Authors: Pablos‐Tanarro, Alba, Lozano‐Ojalvo, Daniel, Martínez‐Blanco, Mónica, Molina, Elena, López‐Fandiño, Rosina
• Format: Article
• Language: English
• Subjects: Adjuvants, Immunologic - pharmacology; Albumen; Allergens; Allergens - immunology; Allergic reactions; Allergies; Animal models; Animals; Antigen presentation; Caco-2 Cells; Children; Cholera Toxin - pharmacology; Dendritic cells; Dendritic Cells - immunology; egg allergy; Egg Hypersensitivity - etiology; Egg White; egg yolk; Egg Yolk - immunology; Female; Humans; IL‐33; Immune system; Intestine; Lymphocytes; Lymphocytes T; Mice; Mice, Inbred BALB C; sensitization; Sensitizing; Stimuli; Th2 Cells - immunology; Th2 responses; Yolk
• ISSN: 1613-4125; 1613-4133
• DOI: 10.1002/mnfr.201800057

Scope Egg is the second most frequent source of allergic reactions in children. Egg yolk (EY) amounts to one‐third in weight of a fresh whole egg, but its contribution to egg allergy has not been investigated in depth. This study assesses whether EY influences the capacity of egg white (EW) to sensitize and trigger allergic responses. Methods and results BALB/c mice were exposed to EW, EY, and their mixture, using models of orally (with and without adjuvant) and adjuvant‐free intraperitoneally induced allergy. In vitro assays were also conducted to examine epithelial and dendritic cell (DC) functions. Results showed that EY played a role during the sensitizing phase of allergy. EY exerted local Th2‐biasing effects through the upregulation of intestinal IL‐33 expression and it also favored Th2 polarization directly during DC presentation of allergens to T cells. Conclusion The results obtained reveal that EY provides Th2‐adjuvant stimuli to the immune system that may increase the susceptibility to develop egg allergy. The joint administration of EW and EY may be a trigger for initiation or maintenance of egg allergy with implications in prevention strategies regarding egg introduction in the diet of susceptible children. BALB/c mice are exposed to egg white, egg yolk, and their mixture, using models of orally (with and without adjuvant) and adjuvant‐free intraperitoneally induced allergy. In vitro assays were also conducted. Results show that egg yolk exerts Th2‐biasing effects through the upregulation of intestinal IL‐33 expression, and it also favors Th2 polarization during dendritic cell presentation of allergens to T cells.