Streptococcus pneumoniae induces exocytosis of Weibel-Palade bodies in pulmonary endothelial cells

Research output: Contribution to journalArticle

Authors

  • Melanie Lüttge
  • Marcus Fulde
  • Susanne R Talay
  • Andreas Nerlich
  • Manfred Rohde
  • Klaus T Preissner
  • Sven Hammerschmidt
  • Michael Steinert
  • Gursharan S Chhatwal
  • Simone Bergmann

Colleges, School and Institutes

Abstract

Invasive pneumococcal infections due to Streptococcus pneumoniae lead to inflammatory infiltration of leucocytes into lung alveolus, meninges and to septic dissemination within the vascular system. The lung microvasculature is covered by pulmonary endothelial cells containing Weibel-Palade bodies (WPB) releasing procoagulant von Willebrand factor (vWF) and other proteins in response to inflammatory stimuli. The influence of pathogenic pneumococci on secretion of WPB proteins is unknown. Here, we report that adherence of S. pneumoniae to primary human pulmonary microvascular endothelial cells (HPMEC) stimulates the WPB exocytosis and the secretion of vWF and interleukin 8 (IL-8). Moreover, infection analyses performed with pneumococcal mutants deficient in the expression of cytotoxic pneumolysin demonstrated that, in addition to direct bacterial adherence, sublytic concentrations of pneumolysin stimulated vWF secretion. The release of vWF was induced after infection with pneumococci from both the apical and the basal cell surfaces, which implies a stimulation of WPB exocytosis in both directions: from inside the vasculature and also following invasive pneumococcal transmigration from pulmonary tissue into the bloodstream. In conclusion, this study demonstrates that the most relevant pulmonary pathogen S. pneumoniae induces release of proinflammatory and procoagulative components directly contributing to pathophysiological processes leading to fatal tissue injury during course of infection.

Bibliographic note

© 2011 Blackwell Publishing Ltd.

Details

Original languageEnglish
Pages (from-to)210-25
Number of pages16
JournalCellular Microbiology
Volume14
Issue number2
Publication statusPublished - Feb 2012

Keywords

  • Bacterial Adhesion, Bacterial Proteins, Cells, Cultured, Endothelial Cells, Exocytosis, Host-Pathogen Interactions, Humans, Interleukin-8, Streptococcus pneumoniae, Streptolysins, Weibel-Palade Bodies, von Willebrand Factor