Identification of potential inflammation markers for outgrowth of cow’s milk allergy

Introduction Immunoglobulin E (IgE)-mediated cow’s milk allergy (CMA) is an immune-mediated reaction to cow’s milk (CM). Non-IgE-mediated CMA resolves in most children in the first years of life, whereas IgE-mediated CMA outgrowth is often later or not at all. The exact mechanisms underlying resolution of IgE-mediated CMA are not fully understood.

We aim to gain insight in the immunological mechanisms underlying resolution of IgE-mediated CMA by analyzing unique saliva samples of allergic infants using the Olink® Target 96 Inflammation panel. Twenty-four children who outgrew their CMA after 12 months were compared to 15 with persistent CMA.

Persistent CMA was accompanied by an increase in interleukin-15 receptor subunit alpha in the first 6 months, followed by a decrease, hinting towards an initial increased T cell response. At the same time caspase-8 was increased and interleukin-7 was decreased in persistent CMA. For CMA resolution, we found elevated levels of delta and notch-like epidermal growth factor-related receptor. Furthermore, adenosine deaminase (ADA) increased significantly between 0 and 12 months in resolved CMA, but not in persistent CMA. KEGG pathway analysis suggests mainly the TNF signaling pathway to be important in the resolution of CM allergy.

Olink® Target 96 Inflammation panel analysis of saliva samples can reveal potential immunological markers and mechanisms involved in CMA resolution. Competing Interest Statement Harm Wopereis is an employee of Danone-Nutricia Research. The project is part of a partnership programme between NWO-TTW and Danone-Nutricia Research. The other authors declare that they have no known conflicts of interest. Footnotes ↵# Shared last authorship Minor revision of abstract; introduction, methods, results and discussion sections extended; supplementary material extended Abbreviations - AAF, - amino acid-based formula; - AAF-syn, - amino acid-based formula supplemented with a synbiotic blend; - ADA, - adenosine deaminase; - CASP-8, - caspase-8; - CM, - cow’s milk; - CMA, - cow’s milk allergy; - CST5, - cystatin D; Ct, threshold cycle; - DNER, - delta and notch-like epidermal growth factor-related receptor; - EN-RAGE, - protein S100-A12; - HGF, - hepatocyte growth factor; - IFN-γ, - interferon gamma; - IgE, - Immunoglobulin E; - IL-1 alpha, - interleukin-1 alpha; - IL-10, - interleukin-10; - IL-15RA, - interleukin-15 receptor subunit alpha; - IL-17, - interleukin-17; - IL-3, - interleukin-3; - IL-4, - interleukin-4; - IL-5, - interleukin-5; - IL-7, - interleukin-7; - IL-8, - interleukin-8; - KEGG, - Kyoto Encyclopedia of Genes and Genomes; - LMM - linear mixed models; - LOD, - limit of detection; - NPX, - Normalized Protein Expression; - OSM, - oncostatin-M; - PEA, - proximity extension assay; - QC, - quality control; - qPCR, - quantitative PCR; - TNF, - tumor necrosis factor; - TNFRSF9, - tumor necrosis factor receptor superfamily member 9; - TNFSF14, - tumor necrosis factor ligand superfamily member 14; - uPA, - urokinase-type plasminogen activator.