title: Neutralization of Neisseria meningitidis outer membrane vesicles.
abstract: BACKGROUND
  We aimed to determine the neutralization of Neisseria meningitidis outer membrane vesicles (blebs) by humoral and cellular elements of whole blood.
  
  
  METHODS
  The interaction of FITC-labeled blebs with monocytes was studied by spectrofluorometry. Blebs are able to induce an oxidative burst in neutrophils, and we evaluated the inhibitory effect of plasma on this process.
  
  
  RESULTS
  Human plasma reduced the priming activity of blebs containing 1-3 ng/ml lipopolysaccharide (LPS) by 50-60% and bactericidal permeability increasing protein (BPI) reduced priming to background levels. A complete neutralization of LPS and blebs by plasma and BPI was measured using the limulus amebocyte lysate (LAL) assay. Furthermore, only 3% of blebs were cell-associated, while the remainder were in the supernatant.
  
  
  CONCLUSIONS
  Plasma and BPI are able to neutralize blebs, with phagocytosis playing only a minor role. As such, we conclude that blebs do not behave like particles but more like free LPS.
authors: Department of Clinical Biochemistry and Molecular Pathology, Medical and Health Science Center, University of Debrecen, Nagyerdei str. 98., Debrecen, 4032, Hungary.
authors: András
authors: A
authors: Vida
authors: Annet
authors: A
authors: Troelstra
authors: Péter
authors: P
authors: Antal-Szalmás
authors: Toon J P
authors: TJ
authors: van Bommel
authors: André F M
authors: AF
authors: Verheul
authors: Jan
authors: J
authors: Verhoef
authors: Kok P M
authors: KP
authors: van Kessel
authors: Jos A G
authors: JA
authors: van Strijp
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