Proteomic Analysis of Exhaled Breath Condensates 

Introduction

Collection of breath condensates is non-invasive, cheap and simple method to obtain patient´s samples. We can determine many different analytes such as proteins, arachidonic acid metabolites, vasoactive peptides amines, DNA, RNA, microRNA and small molecules. These analytes could be the biomarkers used for diagnosis of lung cancer; respiratory, inflammatory, metabolic, cardiac and other systemic diseases. The aim of this study which is done in cooperation with Department of respiratory medicine and Pediatric department is to search for lung cancer, asthma bronchiale and systemic diseases biomarkers in exhaled breath condensate.

Materials/methods

Exhaled breath condensate proteins in the sample are reduced by DTT, alkylated by iodoacetamide, digested by trypsin and concentration of peptides is measured. Samp are purified and diluted for HPLC/ MS analysis which is performed in three technical replicates using high resolution LTQ Orbitrap Elite mass spectrometer (Thermo Scientific). Measured spectra are analyzed by MaxQuant and Perseus software. Data are further statistically evaluated by Statistica and Bioconductor R - package.

Results and conclusions

We initiated pilot study to collect and analyze samples from adult and pediatric patients. Until today we have successfully analyzed the exhaled breath condensate of diagnosed and treated asthma and cystic fibrosis children and compared them with the samples of healthy controls. In the study we have processed 494 samples and have found proteomic biomarkers of asthma. Discovered biomarkers will be validated by MRM mass spectrometry analysis and immunochemical methods. First samples from lung cancer patients were analyzed as well.

This work was supported by grant LF_2015_031 and by the National Sustainability Programme (LO1304)