Pneumologie 2015; 69 - A61
DOI: 10.1055/s-0035-1556653

Transcriptome analysis in endobronchial epithelial lining fluid compared to bronchoalveolar lavage in idiopathic pulmonary fibrosis

N Kahn 1, 2, 3, M Granzow 4, M Meister 2, 3, T Muley 2, 3, FJF Herth 1, 3, M Kreuter 1, 3
  • 1Department of Pneumology and Respiratory Critical Care Medicine, Thoraxklinik at Heidelberg University Hospital, Germany
  • 2Translational Research Unit, Thoraxklinik at Heidelberg University Hospital, Germany
  • 3Translational Lung Research Center (TLRC) Heidelberg, Member of the German Center for Lung Research (DZL), Heidelberg, Germany
  • 4Institute of Human Genetics, University of Heidelberg, Germany

Background: Bronchoscopic Microsampling (BMS) of endobronchial epithelial lining fluid (EELF) might be a potent method for assessing novel molecular biomarkers to improve diagnostics and risk assessment in interstitial lung diseases. In contrast to BAL, EELF can be collected highly localization-specific in the airway of areas with active disease. Aim of this study was to analyze the differences between the transcriptome expression patterns in EELF and BAL samples from patients with IPF.

Methods: EELF was collected from a total of 14 patients by BMS from subsegmental bronchi. BAL from the same patients was sampled from the middle lobe or lingula. Total RNA extraction was performed using AllPrep DNA/RNA Mini Kit (Qiagen). The quantity of total RNA was measured by spectrophotometer (NanoDrop Technologies). The quality of total RNAs was assessed with Agilent 2100 Bioanalyzer. Transcriptome expression analysis was performed with GeneChip® miRNA 3.0 and with Human Transcriptome Array (HTA) 2.0 (both Affymetrix).

Results: All patients underwent BMS and BAL sampling without complications. TotalRNA extraction was reliably performed with all EELF and BAL samples. A total of 40 samples were analyzed for microRNA and mRNA expression. Matched BAL and EELF samples of IPF patients showed 51 highly differentially expressed microRNAs. mRNA expression analysis of BAL and EELF samples also revealed a clear differential expression between both sampling materials in IPF patients.

Conclusions: A significant differential transcriptome expression was detected between BAL and EELF samples of patients with IPF. This indicates that EELF could be an additional biomaterial worth screening for potential biomarkers in IPF.

*Presenting author