Levels of neutrophil elastase and cathepsin B activities, and cystatins in human sputum: relationship to inflammation
Sputum samples from 25 patients with bronchiectasis were assayed enzymatically for myeloperoxidase, neutrophil elastase and cathepsin B, and immunologically for cystatin A, cystatin B, cystatin C, cystatin S and kininogen. High myeloperoxidase and neutrophil elastase levels were found in those sputum samples that were assessed visually to be purulent. These samples were also found to contain high