Human blood basophils do not act as antigen-presenting cells for the major birch pollen allergen Bet v 1.
Allergy
; 67(5): 593-600, 2012 May.
Article
em En
| MEDLINE
| ID: mdl-22188598
ABSTRACT
BACKGROUND:
Several studies in mice have recently shown that basophils can act as antigen-presenting cells (APC) inducing Th2-mediated immune responses against parasites or protease allergens. The aim of this study was to investigate whether human basophils function as APC for the major birch pollen allergen Bet v 1.METHODS:
Fluorescently labeled Bet v 1 was used to assess surface binding and internalization of allergen by basophils and different types of APC from birch pollen-allergic and nonallergic individuals. Sorted basophils were analyzed in terms of up-regulation of MHC class II and co-stimulatory molecules in the absence and presence of IL-3 and IFN-γ by flow cytometry. Expression of proteins crucial for antigen presentation, namely cathepsin S and invariant chain, was determined. Basophils were used as APC in co-culture experiments with Bet v 1-specific T-cell clones (TCCs).RESULTS:
Basophils from birch pollen-allergic donors very efficiently bound Bet v 1 through IgE/FcεRI complexes on their surface. In contrast to professional APC, basophils did not internalize allergen and expressed marginal levels of cathepsin S and invariant chain. HLA-DP, HLA-DQ, CD80/CD86, and CD40 were absent from purified basophils even when stimulated with IL-3 plus IFN-γ. IL-3/IFN-γ marginally up-regulated HLA-DR. Bet v 1-pulsed basophils failed to induce proliferative and cytokine responses in Bet v 1-specific, HLA-DR-restricted TCCs.CONCLUSION:
Human basophils neither internalize, process nor present Bet v 1. Because Bet v 1 is a highly relevant allergen, we conclude that basophils play no role as APC in IgE-mediated allergy in humans.
Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Pólen
/
Basófilos
/
Alérgenos
/
Antígenos de Plantas
/
Células Apresentadoras de Antígenos
Idioma:
En
Revista:
Allergy
Ano de publicação:
2012
Tipo de documento:
Article
País de afiliação:
Áustria