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Effects of sub-lethal concentrations of pneumolysin on the proinflammatory activities of human neutrophils in vitro

Thesis (DPhil)--University of Pretoria, 2005.

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Other Authors: Anderson, Ronald
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Published: University of Pretoria 2013
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access_status_str Open Access
author2 Anderson, Ronald
author_browse Anderson, Ronald
author_facet Anderson, Ronald
collection Thesis
dc_rights_str_mv © 2003 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria.
description Thesis (DPhil)--University of Pretoria, 2005.
format Thesis
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institution University of Pretoria (South Africa)
last_indexed 2026-06-10T12:39:29.475Z
license_str Other — see source repository
provenance_str_mv Harvested via OAI-PMH from UPSpace — University of Pretoria Institutional Repository
publishDate 2013
publishDateRange 2013
publishDateSort 2013
publisher University of Pretoria
publisherStr University of Pretoria
record_format dspace
source_str UPSpace — University of Pretoria Institutional Repository
spelling oai:repository.up.ac.za:2263/28021 Effects of sub-lethal concentrations of pneumolysin on the proinflammatory activities of human neutrophils in vitro Anderson, Ronald upetd@up.ac.za Cockeran, Riana Streptococcus pneumoniae toxins Airway medicine infection Neutrophils Inflammation UCTD Thesis (DPhil)--University of Pretoria, 2005. The Streptococcus pneumoniae-derived toxin, pneumolysin, has been reported to augment neutrophil-mediated inflammatory responses in murine models of experimental infection of the airways, and to favour invasive pneumococcal disease. The laboratory research presented in this thesis has been designed to investigate the possible proinflammatory interactions of pneumolysin with human neutrophils in vitro, as well as the underlying mechanisms of these. Addition of pneumolysin (0.0167 - 41.75 ng/ml) to neutrophils caused dose-related enhancement of the following proinflammatory activities of these cells: superoxide generation, elastase release, expression of the β2-integrin CR3, phospholipase A2 activity and production of leukotriene B4 and prostaglandin E2, oxidative inactivation of α-1-proteinase inhibitor, and synthesis and release of interleukin-8. Pneumolysin-mediated enhancement of these neutrophil activities was observed in the absence of detectable cytotoxicity and was most striking when the toxin was added together with the bacterial chemoattractant N-formyI-L-methionyl-L-leucyl-L-pnenylalanine (FMLP, 1 µM). Treatment of neutrophils with pneumolysin also resulted in uncontrolled influx of Ca2+ into the cells in the setting of membrane depolarisation and efflux of K+, which appeared to be a consequence of the pore forming actions of the toxin. Importantly, the proinflammatory interactions of pneumolysin with neutrophils were completely attenuated by exclusion of Ca2+ from the cell-suspending medium. These observations identify novel proinflammatory properties of pneumolysin which result from pore formation in the plasma membrane, influx of Ca2+ and augmentation of Ca2+ -activitable neutrophil functions. Immunology unrestricted 2013-09-07T12:44:07Z 2005-09-22 2013-09-07T12:44:07Z 2003-04-01 2005-09-22 2005-09-19 Thesis Cockeran, R 2003, Effects of sub-lethal concentrations of pneumolysin on the proinflammatory activities of human neutrophils in vitro, DPhil thesis, University of Pretoria, Pretoria, viewed yymmdd < http://hdl.handle.net/2263/28021 > H1045/ag http://hdl.handle.net/2263/28021 http://upetd.up.ac.za/thesis/available/etd-09192005-110614/ © 2003 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. application/pdf University of Pretoria
spellingShingle Streptococcus pneumoniae toxins
Airway medicine infection
Neutrophils
Inflammation
UCTD
Effects of sub-lethal concentrations of pneumolysin on the proinflammatory activities of human neutrophils in vitro
title Effects of sub-lethal concentrations of pneumolysin on the proinflammatory activities of human neutrophils in vitro
title_full Effects of sub-lethal concentrations of pneumolysin on the proinflammatory activities of human neutrophils in vitro
title_fullStr Effects of sub-lethal concentrations of pneumolysin on the proinflammatory activities of human neutrophils in vitro
title_full_unstemmed Effects of sub-lethal concentrations of pneumolysin on the proinflammatory activities of human neutrophils in vitro
title_short Effects of sub-lethal concentrations of pneumolysin on the proinflammatory activities of human neutrophils in vitro
title_sort effects of sub lethal concentrations of pneumolysin on the proinflammatory activities of human neutrophils in vitro
topic Streptococcus pneumoniae toxins
Airway medicine infection
Neutrophils
Inflammation
UCTD
url http://hdl.handle.net/2263/28021
http://upetd.up.ac.za/thesis/available/etd-09192005-110614/