title: IL-33 promotes the migration and proliferation of circulating fibrocytes from patients with allergen-exacerbated asthma.
abstract: The release of IL-33 increases in the bronchial mucosa of asthmatic patients in relation to disease severity and several studies have demonstrated that IL-33 may enhance airway inflammation in asthma. This study tested the hypothesis that IL-33 may also contribute to the development of irreversible structural changes in asthma by favoring the airway recruitment and profibrotic function of circulating fibrocytes during episodes of allergen-induced asthma exacerbation. The circulating fibrocytes from patients with allergen-exacerbated asthma (PwAA) showed increased expression of the specific IL-33 receptor component ST2L in comparison with the cells from non-asthmatic individuals (NAI). Recombinant IL-33 induced the migration of circulating fibrocytes from PwAA at clinically relevant concentrations and stimulated their proliferation in a concentration-dependent manner between 0.1 and 10 ng/ml, without affecting the constitutive release of type I collagen. The recombinant protein did not induce similar responses in circulating fibrocytes from NAI. This study uncovers an important mechanism through which fibrocytes may accumulate in the airways of allergic asthmatics when their disease is not adequately controlled by current treatment and provides novel information on the function of IL-33 in asthma.
authors.affiliation: Avail Biomedical Research Institute, Basel, Switzerland. lbianchetti@avail-research.com
authors.forename: Lorenza
authors.initials: L
authors.lastname: Bianchetti
authors.forename: Maurizio A
authors.initials: MA
authors.lastname: Marini
authors.forename: Mirko
authors.initials: M
authors.lastname: Isgrò
authors.forename: Alberto
authors.initials: A
authors.lastname: Bellini
authors.forename: Matthias
authors.initials: M
authors.lastname: Schmidt
authors.forename: Sabrina
authors.initials: S
authors.lastname: Mattoli
mesh_terms: D000485:Allergens / Q000276:immunology*; D001249:Asthma / Q000276:immunology* / Q000473:pathology*; D002465:Cell Movement / Q000187:drug effects / Q000276:immunology*; D049109:Cell Proliferation; D018450:Disease Progression; D006801:Humans; D000072179:Interleukin-1 Receptor-Like 1 Protein; D000067596:Interleukin-33; D007378:Interleukins / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D011956:Receptors, Cell Surface / Q000096:biosynthesis*; D011994:Recombinant Proteins / Q000494:pharmacology
chemical_list: D000485:Allergens; C079241:IL1RL1 protein, human; C506536:IL33 protein, human; D000072179:Interleukin-1 Receptor-Like 1 Protein; D000067596:Interleukin-33; D007378:Interleukins; D011956:Receptors, Cell Surface; D011994:Recombinant Proteins