Epitope- and Antigen-Specific IgE Levels May Accurately Predict Peanut Allergy

The use of machine learning algorithms that combine epitope- and antigen-specific immunoglobulin E (IgE) levels in the first 2 to 3 years of life has been associated with improved accuracy in the prediction of developing peanut allergy in children aged ≥4 years.

Researchers conducted a prospective cohort study in a group of high-risk children who were recruited originally for the prospective, observational Consortium for Food Allergy Research (CoFAR2) study. Results of the current analysis were published in the Journal of Allergy and Clinical Immunology.

Investigators sought to assess the evolution of epitope-specific IgE and epitope-specific IgG₄ in a cohort of high-risk infants, to establish whether antibody profiles can predict an individual’s risk for the development of peanut allergy after 4 years of age.

The primary study end point was peanut allergy status at 4 years or older, which involved 5 categories: tolerant status, possible allergy status, convincing allergy status, serologic status (with no known exposure to peanut), and confirmed allergy. A convincing reaction was considered when ≥1 of the following symptoms was reported: (1) presence of hives or angioedema; (2) difficulty breathing, wheezing, or throat tightness; and (3) vomiting within 1 hour of ingestion. Samples were collected from a total of 293 children at aged 3 to 15 months, at aged 2 to 3 years, and at aged ≥4 years.

Results of the study showed that at 4 years or older, 38% of the children evaluated were tolerant vs 14% who had possible, 8% who had convincing, 24% who had serologic, and 16% who had confirmed allergy. Further, children aged 3 to 15 months had epitope-specific profiles that were similar among the groups, whereas distinct increases were observed in children aged 2 and ≥4 years in the confirmed and serologic groups only.

Compared with children in the convincing, possible allergy, and tolerant groups, those in the serologic and confirmed groups demonstrated significantly higher levels of total IgE, as well as IgE specific to peanut Arachis hypogaea (Ara) h 1, Ara h 2, and Ara h 3 proteins (P <.001 for all). Additionally, no significant differences were observed in

peanut-specific (PN-s) IgG₄. Similar patterns in 50 epitope-specific IgE (P <.001) and epitope-specific IgG₄ (P =.218) z-scores were reported.

The investigators concluded that early epitope-specific and peanut-specific IgE predicts peanut allergy status in children aged ≥4 years. If the findings from this study are confirmed, they may help physicians identify infants with persistent peanut allergy in whom early immunotherapeutic interventions should be initiated.

Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.

Reference

Suprun M, Sicherer SH, Wood RA, et al. Early epitope-specific IgE antibodies are predictive of childhood peanut allergy. J Allergy Clin Immunol. Published online August 10, 2020. doi:10.1016/j.jaci.2020.08.005