Periostin as a biomarker in patients with asthma: Associations with eosinophilia and Th2 response

Abstract

Introduction: Periostin is a mesenchymal protein involved in subepithelial fibrosis and airway remodeling in asthma, which is also related to Th2 inflammatory response. Aim: The aim of the study was to measure Periostin levels in serum and induced sputum supernatant of asthmatic patients and healthy subjects and to associate them to inflammatory mediators and disease severity. Methods: 73 patients were enrolled (50 female, median age 58 years [IQR: 45-64]), 41 with severe refractory asthma (SRA) and 32 with mild-to moderate disease. 10 healthy volunteers were also included. Serum samples were collected for Periostin and eosinophil count measurements. Induced sputum was collected for cell count calculation and measurement of Periostin, IFN-γ and ΙL-13 in supernatant. Results: Serum Periostin levels were significantly increased in asthmatics compared to healthy volunteers (28[20-40] vs 19[15-25], p 2 =0.21 and 0.29 respectively, p 2 =0.33, p=0.007). A negative relation was observed between serum Periostin and sputum IFN-γ levels (r 2 =0.26, p Conclusions: Serum Periostin is elevated in asthmatic patients, is associated to disease severity and represents a candidate biomarker of systemic eosinophilic inflammation and airways Th2 inflammatory response.