Immunoglobulin G4 in eosinophilic esophagitis: Immune complex formation and correlation with disease activity

• DOI: 10.1111/all.15826
• Publication Date: 2023-07-27T08:06:29Z
• Authors: Jonathan G. Meder...; Rung‐Chi Li; Xiao‐Yu Zhao; Bocheng Yin; Emily A. Noonan; Elaine F. Etter; Shyam S. Raghavan; Larry C. Borish; Jeffrey M. Wilson; Barrett H. Barnes; Thomas A. E. Plat...; Sarah E. Ewald; Bryan G. Sauer; Emily C. McGowan
• Keywords: Eosinophilic Esophagitis; Immunofluorescence; Immunoprecipitation

Abstract Background Recent studies have shown deposition of immunoglobulin G4 (IgG4) and food proteins in the esophageal mucosa eosinophilic esophagitis (EoE) patients. Our aims were to assess whether co‐localization IgG4 major cow's milk (CMPs) was associated with EoE disease activity investigate enriched proximity deposits. Methods This study included adult subjects ( n = 13) non‐EoE controls 5). Esophageal biopsies immunofluorescence stained for CMPs. Co‐localization paired samples from active remission assessed compared controls. The proteome surrounding deposits evaluated by novel technique, AutoSTOMP. IgG4‐food protein interactions confirmed co‐immunoprecipitation mass spectrometry. Results IgG4‐CMP higher group (Bos d 4, p .02; Bos 5, .002; 8, .002). also significantly .0013; .0007; .0013). AutoSTOMP identified eosinophil‐derived (PRG 2 3, EPX, RNASE3) calpain‐14 IgG4‐enriched areas. Co‐immunoprecipitation spectrometry binding multiple allergens. Conclusion These findings further contribute understanding interaction antigens as it relates activity. data strongly suggest immune complex formation proteins. complexes may a potential role pathophysiology contributing eosinophil activation progression.