Persistent central memory phenotype of circulating Fel d 1 peptide/DRB1*0101 tetramer-binding CD4(+) T cells

Medical Research Council Human Immunology Unit, University of Oxford, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Oxford, United Kingdom.
Journal of Allergy and Clinical Immunology (Impact Factor: 11.25). 01/2007; 118(6):1350-6. DOI: 10.1016/j.jaci.2006.07.040
Source: PubMed

ABSTRACT Although substantial evidence suggests that T cells are important in the pathogenesis of atopic dermatitis (AD), little is known of the differentiation status of CD4+ T cells specific for common environmental allergens.
To determine the frequency, differentiation phenotype, and function of circulating allergen-specific CD4+ T cells in adult individuals with severe persistent AD and controls.
Using tetrameric complexes of an HLA DRB1*0101 restricted epitope from Fel d 1, the major IgE-reactive component of cat dander, we studied ex vivo and cultured T-cell frequency and phenotype in individuals with AD and healthy controls. Cytokine secretion was measured by ex vivo and cultured IFN-gamma, IL-4, and IL-10 enzyme linked immuno-spot analysis.
Ex vivo Fel d 1-specific DRB1*0101-restricted CD4+ T cells express high levels of CCR7, CD62L, CD27, and CD28 and proportionately low levels of tissue-specific homing receptors and TH1 and TH2 cytokine production, placing the cells largely within the central memory subgroup.
Circulating Fel d 1-specific DRB1*0101-restricted CD4+ T cells maintain central memory capacity, consistent with a potential to contribute to persisting clinical atopic disease.
Persisting central memory characteristics of allergen-specific CD4+ T cells in individuals with AD may contribute to chronic disease.

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