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Characterization and epitope identification of the T cell response in non-allergic individuals exposed to mouse allergen.

ABSTRACT: Background:Exposure to airborne allergens is a frequent trigger of respiratory allergy and asthma in atopic individuals. While allergic patients suffer hypersensitivity reactions to these allergens, non-allergic individuals do not exhibit clinical symptoms despite environmental exposure to these ubiquitous allergen sources. The aim of this study was to characterize T cell responses in non-allergic laboratory workers, who are heavily exposed to mice allergens (Exposed Non-Allergics, ENA) and compare this data to previously published T cell responses measured in mouse (MO)-allergic patients. METHODS: Peripheral mononuclear cells (PBMC) from ENA subjects were expanded for 2 weeks in vitro with mouse urine extract and screened for IFN? and IL-5 cytokine production in response to mouse antigen-derived peptides by ELISPOT. Ex vivo T cell reactivity in the ENA cohort was performed after 6hr stimulation with peptide pools by intracellular staining of CD154. Results:Vigorous responses were detected, associated with 147 epitopes derived from 16 mouse antigens. As expected, responses in ENA subjects were somewhat lower than those observed in MO-allergics for both responder frequency and overall response magnitude. While responses in allergics were polarized towards IL-5 production and associated with low IFN? production, ENA responses were not polarized. The composition of targeted antigens and epitopes was overall similar between the two cohorts, with the majority of T cell reactivity directed against Mus m 1 and other major urinary proteins. However, kappa-casein precursor and odorant binding protein Ib were more abundantly recognized in MO-allergics compared to ENA subjects. Additionally, T cell responses against oligopeptides derived from the low molecular weight fraction of mouse urine were also assessed. Interestingly, no difference in the response frequency, magnitude or polarization between MO-allergic and ENA individuals was observed. Finally, assessment of ex vivo T cell activation also revealed T cell reactivity in the ENA cohort, with a non-significant trend for lower responses compared to MO-allergics. Conclusion:Exposure to mouse induces potent T cell responses in non-allergic individuals, targeting similar epitopes as seen in allergic patients.

SUBMITTER: Grifoni A

PROVIDER: S-EPMC6479169 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Characterization and epitope identification of the T cell response in non-allergic individuals exposed to mouse allergen.

Grifoni Alba A da Silva Antunes Ricardo R Westernberg Luise L Pham John J Birrueta Giovanni G Peters Bjoern B Sette Alessandro A Schulten Véronique V

The World Allergy Organization journal 20190420 4

<h4>Background</h4>Exposure to airborne allergens is a frequent trigger of respiratory allergy and asthma in atopic individuals. While allergic patients suffer hypersensitivity reactions to these allergens, non-allergic individuals do not exhibit clinical symptoms despite environmental exposure to these ubiquitous allergen sources. The aim of this study was to characterize T cell responses in non-allergic laboratory workers, who are heavily exposed to mice allergens (Exposed Non-Allergics, ENA) ...[more]

PMID: 31044023

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Characterization and epitope identification of the T cell response in non-allergic individuals exposed to mouse allergen.

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Characterization and epitope identification of the T cell response in non-allergic individuals exposed to mouse allergen.

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