BACKGROUND: Neutrophil elastase (NE) rapidly degrades gel-forming airway mucins in cystic fibrosis (CF) sputum. We hypothesized that KRP-109, a small molecule NE inhibitor, would inhibit CF mucin degradation in vitro. METHODS: Sputa were collected from CF patients (n=5) chronically or intermittently infected with Pseudomonas aeruginosa (P.a.). Mucin degradation was analyzed using western blot. Protease inhibitor studies were performed using alpha1-proteinase inhibitor (A1-PI Prolastin(R)) and KRP-109. Elastase activity assays were performed using spectrophotometry. RESULTS: There were significant differences in the amount of active NE in different CF sputum samples. KRP-109 decreased the NE driven mucin degradation in vitro. Pseudomonas elastases appeared to blunt elastase inhibition by A1-PI or KRP-109. CONCLUSION: Inhibitors of neutrophil and Pseudomonas-derived elastases might rescue mucus clearance and reverse airway obstruction in CF.
- Chillappagari, S.; Muller, C.; Mahavadi, P.; Guenther, A.; Nahrlich, L.; Rosenblum, J.; Rubin, B. K.; Henke, M. O.
Keywords
- Cystic fibrosis
- Mucin
- Protease and anti-protease balance
- Small molecule inhibitors
