BACKGROUND: Our previous studies on intranasal tolerance induction demonstrated reduction of allergic responses with different allergen constructs. The underlying mechanisms varied depending on their conformation or size. OBJECTIVE: The aim of the present study was to compare the uptake of two structurally different allergen molecules within the respiratory tract following intranasal application. METHODS: The three-dimensional Bet v 1 (Bv1-Protein) and the T cell epitope peptide of Bet v 1 (Bv1-Peptide) were labelled with 5,6-Carboxyfluorescein (FAM) and their uptake was investigated in lung cells and cells of the nasal associated lymphoid tissue from naive and sensitised BALB/c mice. Phenotypic characterisation of FAM+ lung cells after antigen incubation in vitro and after intranasal application was performed by flow cytometry. Impact of Bv1-Protein and Bv1-Peptide on cytokine profiles and gene expression in vivo or in an alveolar epithelial type II (ATII) cell line were assessed in mono- and co-cultures with monocytes using ELISA and quantitative real-time PCR. RESULTS: Both antigens were taken up preferably by ATII-like cells (ATII-LCs) in naive mice, and by macrophages in sensitised mice. After intranasal application, Bv1-Peptide was taken up faster and more efficiently than Bv1-Protein. In vivo and in vitro experiments revealed that Bv1-Protein induced the transcription of thymic stromal lymphopoietin mRNA while Bv1-Peptide induced the transcription of IL-10 and MCP1 mRNA in ATII-LCs. CONCLUSION AND CLINICAL RELEVANCE: Both tested antigens were taken up by ATII-LCs under steady state conditions and induced different polarisation of the immune responses. These data may have an important impact for the generation of novel and more effective prophylactic or therapeutic tools targeting the respiratory mucosa.

• MeSH
• Allergens metabolism   MeSH
• Hypersensitivity MeSH
• Antigens, Plant chemistry   MeSH
• Antigens metabolism   MeSH
• Cytokines metabolism   MeSH
• Respiratory System immunology   MeSH
• Epithelial Cells cytology   MeSH
• Epitopes, T-Lymphocyte chemistry   MeSH
• Epitopes chemistry   MeSH
• Phenotype MeSH
• Fluoresceins chemistry   MeSH
• Immune System MeSH
• Real-Time Polymerase Chain Reaction MeSH
• Mice, Inbred BALB C MeSH
• Mice MeSH
• Pulmonary Alveoli cytology   MeSH
• Flow Cytometry MeSH
• Animals MeSH
• Check Tag
• Mice MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• 5,6-dicarboxyfluorescein MeSH Browser
• Allergens MeSH
• Antigens, Plant MeSH
• Antigens MeSH
• Bet v 1 allergen, Betula MeSH Browser
• Cytokines MeSH
• Epitopes, T-Lymphocyte MeSH
• Epitopes MeSH
• Fluoresceins MeSH