Specific inhalation challenge causes minor changes in nasal proteome of work-related asthma patients

Abstract

Background: Changes in airway proteome during specific inhalation challenge are poorly known. Nasal sample could represent the protein profile of entire airways in accordance with the “united airway” concept. Aim: To investigate changes in protein abundances in the upper airways during specific inhalation challenge to different types of occupational agents in subjects with work-related asthma. Methods: Nasal brush samples were collected from 24 non-smoking work-related asthma patients exposed to 1) protein allergens, 2) isocyanates, or 3) welding fumes before specific inhalation challenge. The second sample was collected the day after a specific inhalation challenge to an agent they were exposed at work. Proteome changes were analyzed by two-dimensional difference gel electrophoresis (2D-DIGE), and the found differentially regulated proteins were identified by mass spectrometry. Unsupervised classification analyses (hierarchical clustering and principal component analysis) were applied to data to gain an overview of protein expression patterns. Results: We found clear clustering of the protein allergen, isocyanate and welding fume groups. In all exposure groups, the differences in nasal proteome before and after challenge were small. Conclusions: Minor changes in nasal proteomes were detected during specific inhalation challenge in work-related asthma patients. Our results suggest that proteomic profiles in the airways of work-related asthma patients exposed to different occupational agents are persistent.