Phenotypic analysis of perennial airborne allergen-specific CD4 + T cells in atopic and non-atopic individuals

Journal article

Background Accumulating evidence suggests that T cells play an important role in the pathogenesis of atopic dermatitis (AD); yet, little is known of the differentiation status of CD4 + T cells specific for common environmental allergens, such as the major cat allergen, Fel d 1. Objective To determine the frequency, differentiation phenotype and function of circulating Fel d 1-specific CD4 + T cells in adult individuals with severe persistent AD in comparison with healthy controls. Methods Using HLA class II tetrameric complexes based on a HLA-DPB1 *0401-restricted Fel d 1 epitope, ex vivo and cultured T cell frequency and phenotype were analysed in individuals with AD and healthy controls. Cytokine secretion was measured by ex vivo and cultured IL-4 and IFN-γ ELISpots. Results Ex vivo Fel d 1-specific DPB1 *0401-restricted CD4 + T cells in both atopics and non-atopics express high levels of CCR7, CD62L, CD27 and CD28, placing the cells largely within the central memory subgroup. However, the functional phenotype was distinct, with greater IL-4 production from the cells derived from atopics, which correlated with disease severity. Conclusions and Clinical Relevance Circulating Fel d 1-specific DPB1 *0401-restricted CD4 + T cells in both atopic and non-atopic donors maintain a central memory phenotype; however in atopics, the cells had greater Th2 effector function, compatible with a disease model of altered antigen delivery in atopic individuals. © 2011 Blackwell Publishing Ltd.

Authors: Crack, L; Chan, H; McPherson, T; Ogg, G

• Journal: Clinical and Experimental Allergy
• Volume: 41
• Issue: 11
• Pages: 1555-1567
• Publication date: 2011-11-01
• DOI: 10.1111/j.1365-2222.2011.03819.x
• EISSN: 1365-2222
• ISSN: 0954-7894
• Language: English
• Keywords: Cat allergy; T cell epitope; T cells; Fel d 1; HLA class II tetramer; Atopic dermatitis