Dataset Information

TH1 signatures are present in the lower airways of children with severe asthma, regardless of allergic status.

ABSTRACT: BACKGROUND:The pathogenesis of severe asthma in childhood remains poorly understood. OBJECTIVE:We sought to construct the immunologic landscape in the airways of children with severe asthma. METHODS:Comprehensive analysis of multiple cell types and mediators was performed by using flow cytometry and a multiplex assay with bronchoalveolar lavage (BAL) specimens (n = 68) from 52 highly characterized allergic and nonallergic children (0.5-17 years) with severe treatment-refractory asthma. Multiple relationships were tested by using linear mixed-effects modeling. RESULTS:Memory CCR5+ TH1 cells were enriched in BAL fluid versus blood, and pathogenic respiratory viruses and bacteria were readily detected. IFN-?+IL-17+ and IFN-?-IL-17+ subsets constituted secondary TH types, and BAL fluid CD8+ T cells were almost exclusively IFN-?+. The TH17-associated mediators IL-23 and macrophage inflammatory protein 3?/CCL20 were highly expressed. Despite low TH2 numbers, TH2 cytokines were detected, and TH2 skewing correlated with total IgE levels. Type 2 innate lymphoid cells and basophils were scarce in BAL fluid. Levels of IL-5, IL-33, and IL-28A/IFN-?2 were increased in multisensitized children and correlated with IgE levels to dust mite, ryegrass, and fungi but not cat, ragweed, or food sources. Additionally, levels of IL-5, but no other cytokine, increased with age and correlated with eosinophil numbers in BAL fluid and blood. Both plasmacytoid and IgE+Fc?RI+ myeloid dendritic cells were present in BAL fluid. CONCLUSIONS:The lower airways of children with severe asthma display a dominant TH1 signature and atypical cytokine profiles that link to allergic status. Our findings deviate from established paradigms and warrant further assessment of the pathogenicity of TH1 cells in patients with severe asthma.

SUBMITTER: Wisniewski JA

PROVIDER: S-EPMC5860937 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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T<sub>H</sub>1 signatures are present in the lower airways of children with severe asthma, regardless of allergic status.

Wisniewski Julia A JA Muehling Lyndsey M LM Eccles Jacob D JD Capaldo Brian J BJ Agrawal Rachana R Shirley Debbie-Ann DA Patrie James T JT Workman Lisa J LJ Schuyler Alexander J AJ Lawrence Monica G MG Teague W Gerald WG Woodfolk Judith A JA

The Journal of allergy and clinical immunology 20170920 6

<h4>Background</h4>The pathogenesis of severe asthma in childhood remains poorly understood.<h4>Objective</h4>We sought to construct the immunologic landscape in the airways of children with severe asthma.<h4>Methods</h4>Comprehensive analysis of multiple cell types and mediators was performed by using flow cytometry and a multiplex assay with bronchoalveolar lavage (BAL) specimens (n = 68) from 52 highly characterized allergic and nonallergic children (0.5-17 years) with severe treatment-refrac ...[more]

PMID: 28939412

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Dataset Information

TH1 signatures are present in the lower airways of children with severe asthma, regardless of allergic status.

Publications

T<sub>H</sub>1 signatures are present in the lower airways of children with severe asthma, regardless of allergic status.

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