Fibroblast growth factor-2 is a sputum remodeling biomarker of severe asthma

AbstractObjective: Given the large phenotypic diversity of asthma, our aim was to characterize molecular profiles related to asthma severity using selected remodeling biomarkers in induced sputum. Methods: Induced sputum from healthy controls, patients with mild to moderate asthma and severe asthma were collected. Twelve selected biomarkers previously associated to airway remodeling such as connective tissue growth factor (CTGF), fibroblast growth factor (FGF)-2, matrix metalloproteinase (MMP)-1, MMP-2, MMP-3, MMP-7, MMP-8, MMP-9, MMP-12, MMP-13, procollagen type 1 and tissue inhibitor of metalloproteinase (TIMP)-1 were measured in sputum samples using ELISA or Luminex technology. FGF-2 level was also evaluated in bronchial biopsies using immunohistochemistry. Results: Sputum of severe asthma was characterized by reduced percentage of macrophages and increased percentage of neutrophils and eosinophils. FGF-2, MMP-1 and TIMP-1 levels increased with asthma severity. Interestingly, only FGF-2 level inversely...