title: Clinical Streptococcus pneumoniae isolates induce differing CXCL8 responses from human nasopharyngeal epithelial cells which are reduced by liposomes.
abstract: Streptococcus pneumoniae causes several human diseases, including pneumonia and meningitis, in which pathology is associated with an excessive inflammatory response. A major inducer of this response is the cholesterol dependent pneumococcal toxin, pneumolysin. Here, we measured the amount of inflammatory cytokine CXCL8 (interleukin (IL)-8) by ELISA released by human nasopharyngeal epithelial (Detroit 562) cells as inflammatory response to a 24 h exposure to different pneumococcal strains.
  
  
  
  We found pneumolysin to be the major factor influencing the CXCL8 response. Cholesterol and sphingomyelin-containing liposomes designed to sequester pneumolysin were highly effective at reducing CXCL8 levels from epithelial cells exposed to different clinical pneumococcal isolates. These liposomes also reduced CXCL8 response from epithelial cells exposed to pneumolysin knock-out mutants of S. pneumoniae indicating that they also reduce the CXCL8-inducing effect of an unidentified pneumococcal virulence factor, in addition to pneumolysin.
  
  
  
  The results indicate the potential of liposomes in attenuating excessive inflammation as a future adjunctive treatment of pneumococcal diseases.
authors.affiliation: Faculty of Medicine, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, Bern, CH-3001, Switzerland.
authors.forename: Denja
authors.initials: D
authors.lastname: Baumgartner
authors.affiliation: Faculty of Medicine, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, Bern, CH-3001, Switzerland.
authors.forename: Suzanne
authors.initials: S
authors.lastname: Aebi
authors.affiliation: Faculty of Medicine, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, Bern, CH-3001, Switzerland.
authors.forename: Denis
authors.initials: D
authors.lastname: Grandgirard
authors.affiliation: Faculty of Medicine, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, Bern, CH-3001, Switzerland.
authors.forename: Stephen L
authors.initials: SL
authors.lastname: Leib
authors.affiliation: Faculty of Medicine, Institute of Anatomy, University of Bern, Baltzerstrasse 2, Bern, CH-3012, Switzerland.
authors.forename: Annette
authors.initials: A
authors.lastname: Draeger
authors.affiliation: Faculty of Medicine, Institute of Anatomy, University of Bern, Baltzerstrasse 2, Bern, CH-3012, Switzerland.
authors.forename: Eduard
authors.initials: E
authors.lastname: Babiychuk
authors.affiliation: Faculty of Medicine, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, Bern, CH-3001, Switzerland. lucy.hathaway@ifik.unibe.ch.
authors.forename: Lucy J
authors.initials: LJ
authors.lastname: Hathaway
mesh_terms: D016667:Bacterial Capsules; D001426:Bacterial Proteins / Q000235:genetics / Q000494:pharmacology; D002460:Cell Line; D002478:Cells, Cultured; D002784:Cholesterol / Q000494:pharmacology; D016207:Cytokines / Q000378:metabolism; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism*; D006801:Humans; D016209:Interleukin-8 / Q000378:metabolism*; D008081:Liposomes / Q000494:pharmacology*; D009154:Mutation; D009305:Nasopharynx / Q000187:drug effects / Q000378:metabolism*; D013109:Sphingomyelins / Q000494:pharmacology; D013296:Streptococcus pneumoniae / Q000302:isolation & purification / Q000378:metabolism* / Q000472:pathogenicity; D013301:Streptolysins / Q000235:genetics / Q000494:pharmacology
chemical_list: D001426:Bacterial Proteins; C508606:CXCL8 protein, human; D016207:Cytokines; D016209:Interleukin-8; D008081:Liposomes; D013109:Sphingomyelins; D013301:Streptolysins; C032290:plY protein, Streptococcus pneumoniae; D002784:Cholesterol
keywords: CXCL8; Capsule; Liposomes; Pneumolysin; Streptococcus pneumoniae