Chest ACCP Career Connection
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Guest Access | Sign In via User Name/Password
This Article
Right arrow Full Text Free
Right arrow Full Text (PDF) Free
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Article Archive
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by O’Riordan, T. G.
Right arrow Articles by Simon, S. R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by O’Riordan, T. G.
Right arrow Articles by Simon, S. R.
(Chest. 2005;128:3167-3176.)
© 2005 American College of Chest Physicians

Antiprotease Function of Airway Secretions in Purulent Tracheobronchitis*

Thomas G. O’Riordan, MD; Lori B. Seischab, PhD; Qi-Long Ying, PhD; Eliseo Colon-Carreras, MD; Bilal Chughtari, BA; Lucy B. Palmer, MD, FCCP and Sanford R. Simon, PhD

* From the Departments of Pathology and Biochemistry (Drs. Seischab, Ying, and Simon, and Mr. Chughtari), and Division of Pulmonary/Critical Care Medicine (Drs. Colon-Carreras, Palmer, and O’Riordan), Stony Brook University, Stony Brook, NY.

Correspondence to: Lori B. Seischab, PhD, Department of Biology, 132 Natural Science Building, Western Carolina University, Cullowhee, NC 28723; e-mail: lseischab{at}wcu.edu

Study objectives: Unopposed activity of the serine protease, human leukocyte elastase (HLE), is detectable in the airways of patients with purulent tracheobronchitis. The aim of this study was to assess the compartmentalization of HLE activity in the liquid sol phase and the solid gel phase of airway secretions.

Design: Seventy samples of tracheobrochial aspirates were obtained from patients who had hypersecretion and were receiving mechanical ventilation.

Methods: Samples were separated into sol and gel ("mucous pellet") phases, and HLE activity was measured using chromogenic substrate degradation. HLE was eluted from the mucous pellet using hypertonic saline solution, 1 mol/L, or bovine pancreatic deoxyribonuclease (DNase), 16 µmol/L.

Results: HLE activity partitioned between the sol and gel phases of the secretions, with most of the activity present in the gel phase (32:1 ratio of gel to sol HLE activity). The activity of HLE was 95% inhibited when bound to the gel phase, but activity appeared to be largely restored after elution from the gel phase. The gel phase was capable of binding additional exogenous HLE, and its binding capacity for exogenous HLE was not saturated by concentrations that exceeded the highest clinically relevant HLE levels (1.1 mg/mL). Hypertonic saline solution and DNase I efficiently liberated endogenous and exogenous gel phase-bound HLE activity, suggesting that electrostatic bonds and DNA, respectively, play important roles in binding HLE to the gel phase.

Conclusions: The solid phase of airway secretions is a more important modulator of elastase-antielastase balance than has been previously recognized.

Key Words: bronchitis, chronic • leukocyte elastase • mucus






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2005 by the American College of Chest Physicians.