Secreted proteins from Neisseria meningitidis mediate differential human gene expression and immune activation

Cell Microbiol. 2004 Oct;6(10):927-38. doi: 10.1111/j.1462-5822.2004.00410.x.

Abstract

Meningococcal secreted proteins (MSPs) have been poorly characterized. We hypothesized that MSPs play essential roles in host--bacterial interactions and in the pathogenesis of disease. In order to test this, we examined differential host gene expression in human meningeal-derived cells, in response to endotoxin-depleted MSPs compared to live bacteria. Using expression arrays, upregulated expression of several pro-inflammatory and apoptosis-related genes was found to be induced by MSPs. The transcription and translation of representative genes was confirmed by using various methods. Increased interleukin 8 (IL-8) and cyclooxygenase 2 (COX-2) gene transcription was confirmed using real-time PCR. Upregulated IL-8, IL-6, ICAM-1 and COX-2 protein expression were confirmed by ELISA, flow cytometry or Western immunoblots. Furthermore, exposure of cells to MSPs or live meningococci induced a small significant resistance effect to staurosporine-induced apoptosis. Secreted meningococcal virulence factors are therefore important in inducing host inflammatory responses and resistance to apoptosis, and they are worthy of extensive investigation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis / genetics
  • Bacterial Proteins / metabolism*
  • Cell Survival
  • Cells, Cultured
  • Cyclooxygenase 2
  • Cytokines / genetics
  • Cytokines / metabolism
  • Enzyme Inhibitors / metabolism
  • Gene Expression Profiling*
  • Gene Expression Regulation*
  • Humans
  • Immune System / physiology*
  • Isoenzymes / genetics
  • Isoenzymes / metabolism
  • Lipopolysaccharides / immunology
  • Membrane Proteins
  • Meninges / cytology
  • Meningitis, Meningococcal / immunology
  • Meningitis, Meningococcal / metabolism
  • Meningitis, Meningococcal / microbiology
  • Neisseria meningitidis / metabolism*
  • Oligonucleotide Array Sequence Analysis
  • Prostaglandin-Endoperoxide Synthases / genetics
  • Prostaglandin-Endoperoxide Synthases / metabolism
  • Staurosporine / metabolism

Substances

  • Bacterial Proteins
  • Cytokines
  • Enzyme Inhibitors
  • Isoenzymes
  • Lipopolysaccharides
  • Membrane Proteins
  • lipid-linked oligosaccharides
  • Cyclooxygenase 2
  • PTGS2 protein, human
  • Prostaglandin-Endoperoxide Synthases
  • Staurosporine