THE MAST CELL ACTIVATION TEST (MAT) may help improve understanding of immune responses in children with egg allergy, although its diagnostic performance remains lower than established allergy tests, according to a new study.
Study Examines Responses to Baked and Loosely Cooked Egg
The research investigated how IgE antibody characteristics and IgG4 antibodies influence mast cell activation in children undergoing oral food challenges to baked egg (BE) and loosely cooked egg (LCE).
Accurate diagnosis of egg allergy remains clinically challenging, particularly as many children tolerate baked egg despite reacting to less cooked forms. Oral food challenges are considered the gold standard but are resource intensive and carry the risk of allergic reactions, creating demand for more precise laboratory-based diagnostic tools.
The study analysed 133 children enrolled in the BAT2 egg study who had complete clinical outcomes and samples available for MAT analysis. Participants were categorised according to their response to baked and loosely cooked egg challenges. Among the cohort, 58 children were classified as baked egg allergic (BEA) and 75 as baked egg tolerant (BET), including 16 children allergic to loosely cooked egg.
Researchers assessed MAT performance alongside basophil activation testing (BAT) and examined relationships between mast cell activation and several immunological markers, including egg-specific IgE levels, antibody avidity, specific activity, and IgG4/IgE ratios.
MAT demonstrated moderate ability to distinguish allergic from tolerant children. For baked egg allergy, the test achieved an area under the receiver operating characteristic curve (AUC) of 0.749, with high specificity (89%) but lower sensitivity (52%). Similar performance was observed for loosely cooked egg allergy, with an AUC of 0.704.
Higher IgE Activity Linked to Stronger Mast Cell Responses
Overall diagnostic accuracy for MAT was 68% for both forms of egg allergy, lower than that observed with other diagnostic approaches. However, MAT performance improved in children with higher allergen-specific IgE levels, particularly when IgE concentrations were at least 1 kU/L.
The study also showed that stronger IgE binding characteristics correlated with greater mast cell activation, while higher egg-specific IgG4/IgE ratios were associated with reduced mast cell responses. The authors suggest these findings may help clarify mechanisms underlying allergic tolerance and support future development of targeted therapies for food allergy.
Reference
Houghton V et al. IgE antibody function and mast cell activation to egg in children undergoing baked and loosely cooked egg challenges. Allergy. 2026;DOI: 10.1111/all.70368.
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