title: IL-33 exacerbates eosinophil-mediated airway inflammation.
abstract: IL-33 has emerged as an important mediator in the immunopathogenesis of allergy and asthma. However, the role of IL-33 in eosinophil-mediated inflammation has not been fully explored. In this article, we report that IL-33 directly stimulates eosinophil differentiation from CD117(+) progenitors in an IL-5-dependent manner. Although resting eosinophils expressed moderate levels of the IL-33R alpha-chain (ST2L), eosinophils that accumulated in the airways of mice with OVA-induced asthma expressed increased amounts of ST2L. In vitro, IL-33 and GM-CSF are potent inducers of ST2L expression on eosinophils, and IL-33 induced the production of IL-13, CCL17, and TGF-beta by eosinophils. In adoptive-transfer experiments, IL-33 exacerbated eosinophil-mediated airway inflammation by increasing the levels of eosinophils, macrophages, lymphocytes, IL-13, TGF-beta, CCL3, CCL17, and CCL24 in the lungs. IL-33 also enhanced the eosinophil-mediated differentiation of airway macrophages toward the alternatively activated macrophage phenotype in an IL-13-dependent manner. Taken together, this study demonstrates that the IL-33/ST2 signaling pathway activates airway eosinophils that exacerbate airway inflammation in an autocrine and paracrine manner.
authors.affiliation: Division of Immunology, Infection and Inflammation, Glasgow Biomedical Research Centre, University of Glasgow, Glasgow, United Kingdom.
authors.forename: Bartosz
authors.initials: B
authors.lastname: Stolarski
authors.forename: Mariola
authors.initials: M
authors.lastname: Kurowska-Stolarska
authors.forename: Peter
authors.initials: P
authors.lastname: Kewin
authors.forename: Damo
authors.initials: D
authors.lastname: Xu
authors.forename: Foo Y
authors.initials: FY
authors.lastname: Liew
mesh_terms: D000818:Animals; D019898:Autocrine Communication / Q000235:genetics / Q000276:immunology; D002454:Cell Differentiation / Q000235:genetics / Q000276:immunology; D049109:Cell Proliferation; D002478:Cells, Cultured; D018920:Coculture Techniques; D004804:Eosinophils / Q000276:immunology* / Q000378:metabolism / Q000473:pathology*; D006412:Hematopoietic Stem Cells / Q000276:immunology / Q000473:pathology; D006801:Humans; D018836:Inflammation Mediators / Q000009:adverse effects* / Q000502:physiology*; D000072179:Interleukin-1 Receptor-Like 1 Protein; D000067596:Interleukin-33; D007378:Interleukins / Q000009:adverse effects* / Q000502:physiology*; D008168:Lung / Q000276:immunology* / Q000378:metabolism / Q000473:pathology*; D016131:Lymphocyte Subsets / Q000276:immunology / Q000473:pathology; D008264:Macrophages / Q000276:immunology / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D019899:Paracrine Communication / Q000235:genetics / Q000276:immunology; D018123:Receptors, Interleukin / Q000172:deficiency / Q000235:genetics / Q000502:physiology; D015398:Signal Transduction / Q000235:genetics / Q000276:immunology
chemical_list: C486189:Il1rl1 protein, mouse; C506535:Il33 protein, mouse; D018836:Inflammation Mediators; D000072179:Interleukin-1 Receptor-Like 1 Protein; D000067596:Interleukin-33; D007378:Interleukins; D018123:Receptors, Interleukin