Seasonal proteome changes of nasal mucus reflect perennial inflammatory response and reduced defence mechanisms and plasticity in allergic rhinitis.

INTRODUCTION Nasal mucus and its proteins are a defence against allergens. We sought to investigate dynamic proteome changes in allergic rhinitis upon environmental allergen provocation. METHODS Nasal mucus was collected in and out of pollen season from allergic rhinitis patients (N=10) and healthy controls (N=12). Liquid chromatography-tandem mass spectrometry was performed. Proteins were identified by SwissProt database search and quantified from normalized areas under curve of precursor ion chromatograms. Gene enrichment analysis was performed with Cytoscape/BINGO software. RESULTS In total 430 different proteins were detected in both groups, 203 (47.2%) were newly identified. In allergics CLU and IGKC were significantly more abundant in season (2.2 and 2.1-fold respectively). GSTP1 (0.5-fold), ELANE (0.4-fold), HIST1H2BK (0.3-fold), S100A8 (0.2-fold), S100A12 (0.2-fold) and ARHGDIB (0.1-fold) were significantly less abundant in season. In healthy controls UBC, TUBA1B, HBB and FABP5 were only present in season. Ig kappa chain V-I region DEE (5.3-fold), CLU (5.0-fold), TXN (4.3-fold), MSMB (3.2-fold) and Ig heavy chain V-III region BRO (2.7-fold) were significantly more abundant in season. MUC5B (0.5-fold), SLPI (0.2-fold) and S100P (0.2-fold) were significantly less abundant in season. CONCLUSION Contrary to their symptoms allergic rhinitis patients show perennial inflammatory response lacking adequate reaction to allergens in season. BIOLOGICAL SIGNIFICANCE Many studies dealing with allergic rhinitis are focused on the nasal epithelium. This is the first study to analyse the nasal mucus as primary defence barrier on a proteomic level in and out of pollen season and contrary to the leading opinion shows that allergic patients show a perennial inflammatory response with reduced reaction to allergens whereas healthy controls react on proteome basis towards enhanced defence in season despite lacking allergic sensitization.