IL-33 promotes airway remodeling in pediatric patients with severe steroid-resistant asthma.
J Allergy Clin Immunol 2013;
132:676-685.e13. [PMID:
23759184 DOI:
10.1016/j.jaci.2013.04.012]
[Citation(s) in RCA: 198] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2012] [Revised: 04/08/2013] [Accepted: 04/09/2013] [Indexed: 02/06/2023]
Abstract
BACKGROUND
TH2 cytokines are not responsible for the ongoing symptoms and pathology in children with severe therapy-resistant asthma (STRA). IL-33 induces airway hyperresponsiveness, but its role in airway remodeling and steroid resistance is unknown.
OBJECTIVE
We sought to investigate the relationship between IL-33 and airway remodeling in pediatric patients with STRA.
METHODS
IL-33 levels were quantified in neonatal mice given inhaled house dust mite (HDM), and the effect of blocking IL-13 on remodeling and IL-33 levels was assessed. HDM-induced allergic airways disease (AAD) in neonatal ST2(-/-) mice lacking the IL-33 receptor was assessed, together with collagen production after IL-33 administration. The effect of steroid therapy on IL-33 levels in patients with neonatal AAD was explored. IL-33 expression was quantified in endobronchial biopsy (EB) specimens from children with STRA and related to remodeling, and collagen production by airway fibroblasts from pediatric patients stimulated with IL-33 and budesonide was quantified.
RESULTS
Blocking IL-13 after AAD was established in neonatal mice and did not reduce remodeling or IL-33 levels; airway hyperresponsiveness was only partially reduced. IL-33 promoted collagen synthesis both from asthmatic fibroblasts from pediatric patients and after intranasal administration in mice. Increased cellular expression of IL-33, but not IL-13, was associated with increased reticular basement membrane thickness in EB specimens from children with STRA, whereas remodeling was absent in HDM-exposed ST2(-/-) mice. IL-33 levels were maintained, whereas IL-13 levels were abrogated by steroid treatment in neonatal HDM-exposed mice and in EB specimens from children with STRA.
CONCLUSION
IL-33 is a relatively steroid-resistant mediator that promotes airway remodeling in patients with STRA and is an important therapeutic target.
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