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T cell proliferation and cytokine responses to ovalbumin and ovomucoid detected in children with and without egg allergy
Author(s) -
Tay S. S.,
Clark A. T.,
Deighton J.,
King Y.,
Ewan P. W.
Publication year - 2007
Publication title -
clinical and experimental allergy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.462
H-Index - 154
eISSN - 1365-2222
pISSN - 0954-7894
DOI - 10.1111/j.1365-2222.2007.02807.x
Subject(s) - ovalbumin , egg allergy , immunology , allergy , peripheral blood mononuclear cell , t cell , flow cytometry , allergen , food allergy , peanut allergy , toxoid , medicine , biology , immune system , in vitro , biochemistry , immunization
Summary Background The specific T cell responses in egg allergy and resolution have not been fully elucidated. Objective To characterize egg allergen‐specific T cells of children with active and resolved egg allergy, in comparison with non‐allergic controls. Method We studied children with active ( n =35) or resolved ( n =20) egg allergy determined by oral challenge, and non‐allergic controls ( n =15). Peripheral blood mononuclear cells were labelled with carboxyfluorescein succinimidyl ester (CFSE) and stimulated with ovalbumin (OVA), ovomucoid (OM) or tetanus toxoid. Flow cytometry was used to detect divided CD3 + CFSE lo cells that expressed intra‐cytoplasmic IL‐4 or IFN‐γ. The cell division index (CDI) was calculated as a measure of allergen‐specific proliferation. Peanut‐specific T cells of a subgroup of children who also had peanut allergy were also studied. Results OVA‐specific T cells were found in subjects with active (87%) or resolved (75%) egg allergy and in controls (67%), with a trend towards increased T cell proliferation in allergy. OM‐induced weaker T cell responses than OVA, stimulating fewer responders (46% allergic, 50% resolved, 60% controls) and 10‐fold less proliferation [CDI OVA 2.0 (median), 25.6 (maximum) vs. CDI OM 0.2 (median), 15.1 (maximum); P <0.01]. Both egg allergens induced significant IL‐4 + (median 10%, range 1.4–58%) and IFN‐γ + (median 28%, range 4.5–63%) cells in responders, including non‐allergics. There were no significant differences in IFN‐γ + or IL‐4 + cells or in IFN‐γ/IL‐4 ratios between groups. Peanut‐specific T cell proliferation was significantly higher in peanut allergy [CDI CPE 16.5 (median), 24.8 (maximum)] compared with controls [CDI CPE 2.1 (median), 16.1 (maximum)] but cytokine profiles were not different. Tetanus‐specific T cells were seen in 90% of the subjects, with no significant inter‐group differences in responses. Conclusion Egg allergen‐specific T cells are readily detected in all groups and not restricted to egg allergy. In contrast, peanut‐specific proliferation was significantly higher in peanut allergy. This suggests that T cell responses in peanut and egg allergy may differ. We did not find T helper type 2‐deviated cytokine responses in egg or peanut allergy.