Dataset Information

Egg-specific IgE and basophil activation but not egg-specific T-cell counts correlate with phenotypes of clinical egg allergy.

ABSTRACT: BACKGROUND:Egg allergy is phenotypically heterogeneous. A subset of patients with egg allergy can tolerate egg in an extensively heated form. Inclusion of baked egg (BE) into the diet accelerates resolution of egg allergy. Conversely, BE reactivity is associated with persistent disease. The immune basis of this clinical heterogeneity is unknown. OBJECTIVES:We sought to study egg-specific antibody, basophil, and T-cell responses in children with reactivity or tolerance to BE. METHODS:All participants underwent double-blind, placebo-controlled challenges to BE, and those who tolerated BE were challenged with unheated egg white protein to confirm clinical egg reactivity. Laboratory studies included serum antibody measurements, basophil activation tests, and CD154-based detection of egg-responsive T cells by using flow cytometry. RESULTS:Of the 129 children studied, BE-reactive participants had significantly greater levels of egg-, ovalbumin-, and ovomucoid-specific IgE; lower ratios of egg-specific IgG4/IgE; and increased basophil activation in response to egg. Among all participants, CD154-based profiling revealed egg-responsive T cells producing IL-4 and IL-13 but little IL-10 or IFN-?, as well as the presence of egg-responsive Foxp3+CD25+CD127low regulatory T cells. Egg-responsive T cells expressed CCR4, CCR6, and CXCR5, indicating capacity for homing to the skin, mucosa, and B-cell follicles. However, neither the frequency nor phenotype of egg-responsive T cells was different in those with tolerance or reactivity to BE. CONCLUSIONS:Egg-specific antibody and basophil responses, but not T-cell responses, are greater in those with reactivity versus tolerance to BE. Egg-specific antibody and T-cell responses were highly heterogeneous in this cohort. The clinical implications of this immune heterogeneity will need to be studied longitudinally.

SUBMITTER: Berin MC

PROVIDER: S-EPMC6282170 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Egg-specific IgE and basophil activation but not egg-specific T-cell counts correlate with phenotypes of clinical egg allergy.

Berin M Cecilia MC Grishin Alexander A Masilamani Madhan M Leung Donald Y M DYM Sicherer Scott H SH Jones Stacie M SM Burks A Wesley AW Henning Alice K AK Dawson Peter P Grabowska Joanna J Agashe Charuta C Davidson Wendy F WF Wood Robert A RA Sampson Hugh A HA

The Journal of allergy and clinical immunology 20180305 1

<h4>Background</h4>Egg allergy is phenotypically heterogeneous. A subset of patients with egg allergy can tolerate egg in an extensively heated form. Inclusion of baked egg (BE) into the diet accelerates resolution of egg allergy. Conversely, BE reactivity is associated with persistent disease. The immune basis of this clinical heterogeneity is unknown.<h4>Objectives</h4>We sought to study egg-specific antibody, basophil, and T-cell responses in children with reactivity or tolerance to BE.<h4>Me ...[more]

PMID: 29518422

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Dataset Information

Egg-specific IgE and basophil activation but not egg-specific T-cell counts correlate with phenotypes of clinical egg allergy.

Publications

Egg-specific IgE and basophil activation but not egg-specific T-cell counts correlate with phenotypes of clinical egg allergy.

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