JACI:IgG4 Component Allergens Are Preferentially Increased in Eosinophilic Esophagitis As Compared to Patients with Milk Anaphylaxis or Galactose-Alpha-1,3-Galactose Aller
[IF:13.1]
DOI: https://doi.org/10.1016/j.jaci.2015.12.780 Abstract: Rationale Incidence of food allergy is increasing, including diseases with apparently unique pathophysiologic pathways such as eosinophilic esophagitis (EoE), milk anaphylaxis and galactose-alpha-1,3-galactose (alpha-gal) allergy. The role of IgE in these diseases has been well studied, though the contribution of other antibody subtypes, including IgG4, is less clear. Methods Here we assessed IgG4 levels to relevant component allergens from sera banked at the University of Virginia in randomly selected patients carrying diagnoses of EoE, milk anaphylaxis and alpha-gal meat allergy. IgG4 and IgE levels were measured with ImmunoCap technology using commercial assays or biotinylated antigen coupled to streptavidin immunosorbent. Results IgG4 geometric mean levels to milk component allergens Bos d 4 (α-lactalbumin) and Bos d 5 (β-lactoglobulin) were >10 fold higher in EoE patients than milk anaphylaxis or non-allergic controls. This also correlated with a pronounced shift in the IgE/IgG4 ratio between EoE and milk anaphylaxis. Similar to the trend seen in milk anaphylaxis but contrary to EoE, alpha-gal patients had marked relative increase in IgE versus IgG4 levels to the relevant allergen galactose-alpha-1,3-galactose. Conclusions Levels of IgG4 to relevant allergen are uniquely elevated in EoE as compared to other food allergies, including milk anaphylaxis and alpha-gal, where IgE is the dominant response. This preliminary work using component-specific testing builds on prior studies demonstrating that IgG4 is preferentially elevated in EoE. It also highlights that despite a delayed clinical response alpha-gal shares an IgE-to-IgG4 signature similar to other immediate hypersensitivity reactions. All Authors Jeffrey M. Wilson Alexander J. Schuyler Anubha Tripathi Elizabeth A. Erwin Scott P. Commins Thomas A.E. Platts-Mills