Dasgupta A, Chakraborty R, Saha B, et al. - Researchers assessed the profile of sputum proteins in various airway diseases, by analyzing sputum from 31 patients with various airway diseases. Of 185 proteins quantitated by SWATH (sequential window acquisition of all theoretical fragments ion spectra), 21 could differentiate between the clinical phenotypes by hierarchical clustering. Four groups were suggested by functional protein clustering: those that are inflammation related, oxidative stress related, mucin related and a cytoskeletal and calcium related group. Findings showed that identification of various airway disease clinical phenotypes was enabled by sputum proteins. The identified biomarkers for frequent exacerbators included: total protein concentration and eight other proteins (Azurocidin1, Neutrophil defensin 3, Lactotransferrin, Calmodulin 3, Coronin1A, Mucin 5B, Mucin 5AC and BPI fold containing family B1).