Return to content in this issue

 

Fecal IgE Analyses Reveal a Role for Stratifying Peanut-Allergic Patients

Czolk R1,2, Codreanu-Morel F3, de Nies L2,4, Busi SB4,5, Halder R4, Hunewald O1, Boehm TM1,2, Hefeng FQ1, De Beaufort C2,4,6, Wilmes P2,4, Ollert M1,7, Kuehn A1

1Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette, Luxembourg
2Department of Life Science and Medicine, Faculty of Science, Technology and Medicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
3National Unit of Immunology and Allergology, Centre Hospitalier de Luxembourg, Luxembourg, Luxembourg
4Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
5UK Centre for Ecology and Hydrology, Wallingford, Oxfordshire, United Kingdom
6Diabetes and Endocrine Care Clinique Pédiatrique, Clinique Pédiatrique, Centre Hospitalier de Luxembourg, Luxembourg
7Department of Dermatology and Allergy Center, Odense Research Center for Anaphylaxis, Odense University Hospital, University of Southern Denmark, Odense, Denmark

J Investig Allergol Clin Immunol 2025; Vol. 35(4)
doi: 10.18176/jiaci.1008

Background: Peanut allergy (PA) is an IgE-mediated food allergy with variable clinical outcomes. Mild-to-severe symptoms affect various organs and, often, the gastrointestinal tract. The role of intestine-derived IgE antibodies in gastrointestinal PA symptoms is poorly understood.
Objective: This study aimed to examine fecal IgE responses in PA as a novel approach to patient endotyping.
Methods: Feces and serum samples were collected from peanut-allergic and healthy children (n=26) to identify IgE and cytokines using multiplex assays. Shotgun metagenomics DNA sequencing and allergen database comparisons made it possible to identify microbial peptides with homology to known allergens.
Results: Compared to controls, fecal IgE signatures showed broad diversity and increased levels for 13 allergens, including food, venom, contact, and respiratory allergens (P<.01-.0001). Overall, fecal IgE patterns were negatively correlated compared to sera IgE patterns in PA patients, with the greatest differences recorded for peanut allergens (P<.0001). For 83% of the allergens recognized by fecal IgE, we found bacterial homologs from PA patients’ gut microbiome (eg, thaumatin-like protein Acinetobacter baumannii vs Act d 2, 109/124 aa identical). Compared to controls, PA patients had higher levels of fecal IgA, IL-22, and auto-IgE binding to their own fecal proteins (P<.001). Finally, levels of fecal IgE correlated with abdominal pain scores (P<.0001), suggesting a link between local IgE production and clinical outcomes.
Conclusion: Fecal IgE release from the intestinal mucosa could be an underlying mechanism of severe abdominal pain through the association between leaky gut epithelia and anticommensal TH2 responses in PA.

Key words: Abdominal pain, Gut microbiome, IgE, Phenotype, Peanut allergy