title: The role of circulating food antigen-specific lymphocytes in food allergic children with atopic dermatitis.
abstract: In this study we evaluated antigen-specific in vitro responses of peripheral blood lymphocytes to lipopolysaccharide (LPS)-depleted food allergens in children who reacted to food challenge (cow's milk or hen's egg) with a deterioration of their atopic dermatitis (AD). Some of the children showed immediate symptoms (urticaria, bronchial asthma or gastrointestinal symptoms) as well. The proliferation of casein-stimulated lymphocytes from children reacting to cow's milk (age 0.7-5.9 years) was significantly higher (P < 0.01) than the proliferation of lymphocytes from 15 children with AD without milk allergy (age: 2.1-9.1 years). Twenty-eight T-cell clones (TCC) were established from the blood of three children sensitized to cow's milk and hen's egg who reacted to double-blind, placebo-controlled oral food challenge both with a deterioration of AD and with immediate symptoms. Surprisingly, 16 of 28 casein- or ovalbumin-specific TCC were CD8+. All TCC produced high amounts of IFN-gamma upon stimulation with concanavalin A. In addition, 75% of the CD4+ TCC and 44% of the CD8+ TCC secreted IL-4. Our results indicate that: (i) food-specific proliferation of blood lymphocytes can be detected in patients with clinically relevant food allergy with LPS-depleted allergens in vitro and (ii) circulating food-specific lymphocytes are CD4+ and CD8+ T cells with the capacity of producing both type 1 and type 2 cytokines.
authors.affiliation: Department of Dermatology, Hannover Medical School, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Reekers
authors.forename: K
authors.initials: K
authors.lastname: Beyer
authors.forename: B
authors.initials: B
authors.lastname: Niggemann
authors.forename: U
authors.initials: U
authors.lastname: Wahn
authors.forename: J
authors.initials: J
authors.lastname: Freihorst
authors.forename: A
authors.initials: A
authors.lastname: Kapp
authors.forename: T
authors.initials: T
authors.lastname: Werfel
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D003208:Concanavalin A; D003876:Dermatitis, Atopic / Q000276:immunology*; D004311:Double-Blind Method; D004531:Eggs / Q000009:adverse effects*; D005512:Food Hypersensitivity / Q000276:immunology*; D006801:Humans; D007159:Immunologic Tests; D007223:Infant; D007371:Interferon-gamma / Q000378:metabolism; D015847:Interleukin-4 / Q000378:metabolism; D008213:Lymphocyte Activation; D008892:Milk / Q000009:adverse effects*; D016269:Milk Hypersensitivity / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D003208:Concanavalin A; D015847:Interleukin-4; D007371:Interferon-gamma