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Article: Sputum stimulation of human neutrophil degradation of lung proteoglycans

TitleSputum stimulation of human neutrophil degradation of lung proteoglycans
Authors
Issue Date1998
PublisherAmerican College of Chest Physicians. The Journal's web site is located at http://www.chestjournal.org
Citation
Chest, 1998, v. 114 n. 4 SUPPL., p. 250S How to Cite?
AbstractPurpose: Neutrophil-mediated matrix degradation was proposed to be a pathogenetic factor in bronchiectasis. In this study we test for the degradation of lung proteoglycans in a model matrix when neutrophils are activated by pro-inflammatory mediators in bronchial secretions. Methods: Proteoglycans isolated from rat lungs were entrapped in 5 % polyacrylamide gel beads as a model matrix for incubation with either normal human neutrophils and/or sputum sol from patients with bronchiectasis. When proteoglycans were degraded, fragments containing glycosaminoglycans released into the incubation medium and were assayed for hexuronate content. Proteoglycan degradation is indicated when there was an increase in hexuronate content when compared with control incubations. The data represent mean ± SD of five independent experiments performed in duplicate. Results: Blank incubations of neutrophils and sputum sol gave hexuronate concentration of (6.52±1.02) μg/ml and (8.72±1.25) μg/ml respectively. Single incubations with gel beads showed increase hexuronate contents of (8.47±1.18) μg/ml and (10.04±1.94) μg/ml respectively. This indicated that both sputum sol from patients with bronchiectasis and neutrophils from normal volunteers exhibited basal proteoglycan-degrading activity. Combined incubation of sputum sol and neutrophils with gel beads showed further increase in hexuronate concentration to (27.95±1.70) μg/ml. The stimulation was neutralized to (16.42±0.32) μg/ml by antibody against TNFα, a pro-inflammatory mediator found in sputum sol of patients with bronchoectasis. Eglin C, a serine protease inhibitors of neutrophil elastase and cathepsin G, was found to lower neutrophil-mediated proteoglycan degradation to hexuronate concentration of (15.07±0.66) μg/ml in the medium. The results suggest that serine protease secreted by neutrophils may degrade proetoglycans in a model matrix and this secretion is stimulated by TNFα in bronchial secretions of patients with bronchiectasis. Conclusions: Our preliminary experiment suggest that sputum sol are able to stimulate neutrophil-mediated proteoglycan degradation. Besides, TNFα in sputum sol are able to enhance the effect of neutrophil-mediated proteoglycan degradation. We postulate that cytokine may play a role in this process. Clinical Implications: Understanding of mechanisms of tissue degradation can contribute to therapeutic strategy that prevents long term lung damage leading to respiratory failure.
Persistent Identifierhttp://hdl.handle.net/10722/147552
ISSN
2015 Impact Factor: 5.94
2015 SCImago Journal Rankings: 3.176

 

DC FieldValueLanguage
dc.contributor.authorChan, CHen_HK
dc.contributor.authorShum, KYen_HK
dc.contributor.authorIp, MSen_HK
dc.date.accessioned2012-05-29T06:04:32Z-
dc.date.available2012-05-29T06:04:32Z-
dc.date.issued1998en_HK
dc.identifier.citationChest, 1998, v. 114 n. 4 SUPPL., p. 250Sen_HK
dc.identifier.issn0012-3692en_HK
dc.identifier.urihttp://hdl.handle.net/10722/147552-
dc.description.abstractPurpose: Neutrophil-mediated matrix degradation was proposed to be a pathogenetic factor in bronchiectasis. In this study we test for the degradation of lung proteoglycans in a model matrix when neutrophils are activated by pro-inflammatory mediators in bronchial secretions. Methods: Proteoglycans isolated from rat lungs were entrapped in 5 % polyacrylamide gel beads as a model matrix for incubation with either normal human neutrophils and/or sputum sol from patients with bronchiectasis. When proteoglycans were degraded, fragments containing glycosaminoglycans released into the incubation medium and were assayed for hexuronate content. Proteoglycan degradation is indicated when there was an increase in hexuronate content when compared with control incubations. The data represent mean ± SD of five independent experiments performed in duplicate. Results: Blank incubations of neutrophils and sputum sol gave hexuronate concentration of (6.52±1.02) μg/ml and (8.72±1.25) μg/ml respectively. Single incubations with gel beads showed increase hexuronate contents of (8.47±1.18) μg/ml and (10.04±1.94) μg/ml respectively. This indicated that both sputum sol from patients with bronchiectasis and neutrophils from normal volunteers exhibited basal proteoglycan-degrading activity. Combined incubation of sputum sol and neutrophils with gel beads showed further increase in hexuronate concentration to (27.95±1.70) μg/ml. The stimulation was neutralized to (16.42±0.32) μg/ml by antibody against TNFα, a pro-inflammatory mediator found in sputum sol of patients with bronchoectasis. Eglin C, a serine protease inhibitors of neutrophil elastase and cathepsin G, was found to lower neutrophil-mediated proteoglycan degradation to hexuronate concentration of (15.07±0.66) μg/ml in the medium. The results suggest that serine protease secreted by neutrophils may degrade proetoglycans in a model matrix and this secretion is stimulated by TNFα in bronchial secretions of patients with bronchiectasis. Conclusions: Our preliminary experiment suggest that sputum sol are able to stimulate neutrophil-mediated proteoglycan degradation. Besides, TNFα in sputum sol are able to enhance the effect of neutrophil-mediated proteoglycan degradation. We postulate that cytokine may play a role in this process. Clinical Implications: Understanding of mechanisms of tissue degradation can contribute to therapeutic strategy that prevents long term lung damage leading to respiratory failure.en_HK
dc.languageengen_US
dc.publisherAmerican College of Chest Physicians. The Journal's web site is located at http://www.chestjournal.orgen_HK
dc.relation.ispartofChesten_HK
dc.titleSputum stimulation of human neutrophil degradation of lung proteoglycansen_HK
dc.typeArticleen_HK
dc.identifier.emailShum, KY:shumdkhk@hkucc.hku.hken_HK
dc.identifier.emailIp, MS:msmip@hku.hken_HK
dc.identifier.authorityShum, KY=rp00321en_HK
dc.identifier.authorityIp, MS=rp00347en_HK
dc.description.naturelink_to_subscribed_fulltexten_US
dc.identifier.scopuseid_2-s2.0-33750265904en_HK
dc.identifier.volume114en_HK
dc.identifier.issue4 SUPPL.en_HK
dc.identifier.spage250Sen_HK
dc.identifier.epage250Sen_HK
dc.publisher.placeUnited Statesen_HK
dc.identifier.scopusauthoridChan, CH=7404813351en_HK
dc.identifier.scopusauthoridShum, KY=7004824447en_HK
dc.identifier.scopusauthoridIp, MS=7102423259en_HK

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