124years, further attempts have been made to precisely identify these phenotypes, and this has initiated a search for new reliable biomarkers. Periostin has been found to be a marker for Th2-associated inflammation in patients with asthma.
1This type of inflammation is associated with an increased eosinophil count not only in peripheral blood, but also in bronchoalveolar lavage fluid (BALF).2 Therefore, periostin may be used as a potential predictor of airway eosinophilia.
3IntroductIon Asthma is a chronic inflammatory disease with a complex immunological background. Eosinophils are the main cells involved in asthma-related airway inflammation; however, there is also a significant contribution of neutrophils, lymphocytes, and mast cells. As the type of inflammation has been shown to affect treatment response, determination of asthma inflammatory phenotypes based on the predominant inflammatory cells has been strongly advocated. In recent
AbstrActIntroductIon Periostin is considered to be a marker of eosinophilic inflammation in patients with asthma. However, there are no literature data on periostin in patients with chronic obstructive pulmonary disease (COPD).objectIves The aim of the study was to evaluate periostin expression and to compare its concentrations in various materials in patients with mild-to-moderate asthma and COPD, as well as to evaluate the potential association between periostin and clinical features of both diseases.
PAtIents And methodsUsing an enzyme-linked immunosorbent assay, we measured periostin concentrations in serum, induced sputum (IS), exhaled breath condensate (EBC), and bronchoalveolar lavage fluid (BALF) as well as periostin expression in bronchial biopsy samples in 24 patients with asthma, 36 patients with COPD, and 12 controls. Correlations between periostin levels in different materials were also analyzed and periostin concentrations were compared between patients with asthma and those with COPD.results Periostin levels were detectable in serum, IS, EBC, and BALF from patients with asthma, COPD, and controls. EBC periostin levels correlated with tissue periostin expression and were significantly higher in asthma than in COPD (P = 0.04). Periostin expression in bronchial mucosa was higher in asthma than in COPD (P <0.001), as well as in asthma and COPD patients compared with controls (P <0.001). No significant correlations between tissue periostin expression and BALF, IS, or serum periostin levels were found. There were no differences in serum, IS, BALF, or EBC periostin concentrations between patients with different phenotypes of both diseases.conclusIons Periostin may be detected not only in serum, IS, and airway tissue samples, but also in EBC and BALF. EBC periostin levels and tissue periostin expression are higher in patients with asthma than in those with COPD. EBC periostin levels may serve as a potential surrogate marker for tissue periostin expression.
125Patients were recruited from an outpatient clinic and included consecutive patients with asthma and COPD who wer...