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Identification of Inositol Phosphate or Phosphoinositide Interacting Proteins by Affinity Chromatography Coupled to Western Blot or Mass Spectrometry
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Polyphosphoinositides suppress the adhesion of Haemophilus influenzae to pharyngeal cells

Jim-Wen R Liu1, Steve N Anderson, Jonathan A Meulbroek

  • 1Ross Products Division, Abbott Laboratories, 625 Cleveland Ave, Columbus, OH 43216, USA. jim-wen.liu@abbott.com

Lipids in Health and Disease
|September 7, 2004
PubMed
Abstract

Insights

Phosphoinositides like PI-3,4-PP show promise as anti-adhesion agents against Haemophilus influenzae (HI), a common cause of otitis media. This research suggests these compounds could offer a new prophylactic treatment to prevent HI adhesion and colonization.

Area of Science:

  • Microbiology
  • Biochemistry
  • Pharmacology

Background:

  • Otitis media (OM), a middle ear inflammation common in children, is frequently caused by Haemophilus influenzae (HI).
  • Antibiotic treatments for OM are increasingly challenged by bacterial resistance.
  • Anti-adhesion agents are being explored as alternative prophylactic strategies against bacterial infections.

Purpose of the Study:

  • To investigate the potential of phosphoinositides as anti-adhesion agents against Haemophilus influenzae.
  • To evaluate the efficacy of specific phosphoinositides in preventing HI adhesion to host cells.
  • To assess the in vivo effectiveness of promising phosphoinositides in preventing HI colonization.

Main Methods:

  • Radiolabeling of non-typeable HI cells with 111-indium-oxine.
  • Pre-incubation of HI cells with various phosphoinositides.
  • Incubation of treated HI cells with a human pharynx carcinoma (DT 562) cell monolayer.
  • In vivo study involving neonatal rats to assess HI growth suppression.

Main Results:

  • Dipalmitoylphosphatidylinositol-3,4-diphosphate (PI-3,4-PP) demonstrated the highest anti-adhesion activity against HI cells at 0.1 mg/mL.
  • Phosphatidylinositol-3-phosphate (PI-3-P) and phosphatidylinositol-4-phosphate (PI-4-P) also exhibited anti-adhesion properties.
  • PI-3,4-PP's anti-adhesion effect was dose-dependent.
  • In vivo, PI-3,4-PP significantly suppressed HI growth in the nasopharynx of neonatal rats.

Conclusions:

  • PI-3-P, PI-4-P, and particularly PI-3,4-PP show potential as prophylactic agents.
  • These phosphoinositides may effectively inhibit HI adhesion and colonization.
  • The findings support the development of phosphoinositide-based therapies for preventing HI infections.

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