gp96 expression in neutrophils is critical for the onset of Escherichia coli K1 (RS218) meningitis

Nat Commun. 2011 Nov 22:2:552. doi: 10.1038/ncomms1554.

Abstract

Despite the fundamental function of neutrophils (polymorphonuclear leukocytes (PMNs)) in innate immunity, their role in Escherichia coli K1 (EC-K1) -induced meningitis is unexplored. Here we show that PMN-depleted mice are resistant to EC-K1 (RS218) meningitis. EC-K1 survives and multiplies in PMNs for which outer membrane protein A (OmpA) expression is essential. EC-K1 infection of PMNs increases the cell surface expression of gp96, which acts as a receptor for bacterial entry. Suppression of gp96 expression in newborn mice prevents the onset of EC-K1 meningitis. Infection of PMNs with EC-K1 suppresses oxidative burst by downregulating rac1, rac2 and gp91(phox) transcription both in vitro and in vivo. The interaction of loop 2 of OmpA with gp96 is essential for EC-K1-mediated inhibition of oxidative burst. These results reveal that EC-K1 exploits surface-expressed gp96 in PMNs to prevent oxidative burst for the onset of neonatal meningitis.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Animals, Newborn
  • Cells, Cultured
  • Escherichia coli / immunology*
  • Escherichia coli / metabolism
  • Escherichia coli / pathogenicity*
  • Female
  • Flow Cytometry
  • Humans
  • Male
  • Membrane Glycoproteins / genetics
  • Membrane Glycoproteins / metabolism*
  • Meningitis, Bacterial / genetics
  • Meningitis, Bacterial / immunology*
  • Meningitis, Bacterial / metabolism*
  • Mice
  • Mice, Inbred C57BL
  • Neutrophils / metabolism*
  • Neutrophils / microbiology*
  • RNA, Small Interfering
  • Reverse Transcriptase Polymerase Chain Reaction

Substances

  • Membrane Glycoproteins
  • RNA, Small Interfering
  • endoplasmin