Abstract

Respiratory disorders in sulfur mustard (SM)-exposed and chronic obstructive pulmonary disease (COPD) patients are mostly associated with neutrophilic inflammation, severe airflow limitation, and oxidative stress. The objective of this study was to establish whether neutrophil (PMN) proteomes in these diseases were similar or differed. Blood neutrophil proteomes from healthy, SM-exposed, and COPD subjects were analyzed using two-dimensional gel electrophoresis followed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI TOF MS). Elastase activity was determined kinetically. The results showed that levels of S100 calcium-binding protein (CBP) A12, S100 CBP A8, glyceraldehyde-3-phosphate dehy-drogenase, superoxide dismutase, and protein disulfide isomerase proteins as well as elastase activity - were significantly increased in PMN from 'diseased' hosts compared to in cells from healthy controls. In contrast, coactosin-like protein, RhoGDP dissociation inhibitor, and actin isoforms were significantly decreased in diseased subjects' PMN compared to PMN of healthy controls. Moreover, serpin B1 and coronin-1A were expressed only in PMN of the healthy subjects. Lastly, S100 CBP A9, endoplasmic reticulum (ER)-60 protease, and glutathione-S-transferase isoforms were differentially expressed in the cells from the SM-exposed and COPD subjects. These results show that serpin B1, an efficient inhibitor of neutrophil serine proteases, was not detectable, and elastase activity significantly increased in PMN from both SM-exposed and COPD patients. It seems that, apart from inflammation and oxidative stress, a protease: anti-protease imbalance exists within PMN of both COPD and SM-exposed patients.