Abstract
Introduction: IL27, a cytokine produced by antigen presenting cells (APCs) is one of the early factors driving Th1 polarization of lymphocytes. In spite of numerous studies, it seems the present knowledge about IL27 expression in lower airways is still deficient.
Aim: To determine sources of IL27 in human lower airways in BAL in interstitial lung diseases (ILD) patients.
Materials and Methods: The local sources of IL27 were determined in BAL cells by indirect phenotyping and flow cytometry. IL27 concentration in BAL supernatants was examined by ELISA. Cells and supernatants were collected from patients with PS (n=13, 3 steroid treated subjects), idiopathic pulmonary fibrosis (IPF, n=3), nonspecific interstitial pneumonia (NSIP, n=5), exogenous allergic alveolitis (EAA, n=3) and controls (n=3).
Results: Alveolar macrophages were proved positive for intracellular IL27 expression. The IL27 intracellular staining proved positive also for AL in almost all ILD patients (n=22) and in controls (n=3). IL27+ AL were detected in BAL material from PS (n=10, 89±15.5, 49-100%; all results as median±SEM, range), EAA (21±8.7, 11-23%) and NSIP (75±6.5, 54-85%) patients and in controls (46±15.0, 7-85%). IL27 was also detected in BAL supernatants by ELISA in 6 out of 10 steroid-naive PS patients (4.46±1.83, 0-15.49 pg/ml).
Conclusions: We provided strong preliminary data suggesting IL27 expression by AL and propose that IL27 is secreted in lower airways not exclusively by APCs. Its increased expression in PS suggests IL27 to play a role in ILD pathophysiology, probably as Th1 activity marker.
- © 2013 ERS
