Ana o 1 and Ana o 2 cashew allergens share cross-reactive CD4(+) T cell epitopes with other tree nuts.
Clin Exp Allergy
; 46(6): 871-83, 2016 06.
Article
em En
| MEDLINE
| ID: mdl-27129138
ABSTRACT
BACKGROUND:
Allergies to cashew are increasing in prevalence, with clinical symptoms ranging from oral pruritus to fatal anaphylactic reaction. Yet, cashew-specific T cell epitopes and T cell cross-reactivity amongst cashew and other tree nut allergens in humans remain uncharacterized.OBJECTIVES:
In this study, we characterized cashew-specific T cell responses in cashew-allergic subjects and examined cross-reactivity of these cashew-specific cells towards other tree nut allergens.METHODS:
CD154 up-regulation assay was used to determine immunodominance hierarchy among cashew major allergens at the T cell level. The phenotype, magnitude and functionality of cashew-specific T cells were determined by utilizing ex vivo staining with MHC class II tetramers. Dual tetramer staining and proliferation experiments were used to determine cross-reactivity to other tree nuts.RESULTS:
CD4(+) T cell responses were directed towards cashew allergens Ana o 1 and Ana o 2. Multiple Ana o 1 and Ana o 2 T cell epitopes were then identified. These epitopes elicited either TH 2 or TH 2/TH 17 responses in allergic subjects, which were either cashew unique epitope or cross-reactive epitopes. For clones that recognized the cross-reactive epitope, T cell clones responded robustly to cashew, hazelnut and/or pistachio but not to walnut.CONCLUSIONS:
Phylogenetically diverse tree nut allergens can activate cashew-reactive T cells and elicit a TH 2-type response at an epitope-specific level. CLINICAL RELEVANCE Lack of cross-reactivity between walnut and cashew suggests that cashew peptide immunotherapy approach may not be most effective for walnut.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Plantas
/
Alérgenos
/
Linfócitos T CD4-Positivos
/
Epitopos de Linfócito T
/
Reações Cruzadas
/
Antígenos de Plantas
/
Nozes
Tipo de estudo:
Diagnostic_studies
/
Prognostic_studies
/
Risk_factors_studies
Limite:
Adolescent
/
Adult
/
Child
/
Female
/
Humans
/
Male
Idioma:
En
Revista:
Clin Exp Allergy
Assunto da revista:
ALERGIA E IMUNOLOGIA
Ano de publicação:
2016
Tipo de documento:
Article
País de afiliação:
Estados Unidos