Related Experiment Video

Updated: Aug 19, 2026

Implementation of a Permeable Membrane Insert-based Infection System to Study the Effects of Secreted Bacterial Toxins on Mammalian Host Cells
09:25

Implementation of a Permeable Membrane Insert-based Infection System to Study the Effects of Secreted Bacterial Toxins on Mammalian Host Cells

Published on: August 19, 2016

Effect of Staphylococcus aureus bacteria and bacterial toxins on meningeal permeability in vitro

W C Ummenhofer1, A E Stapleton, C M Bernards

  • 1Department of Anesthesiology, University of Washington, Seattle 98195, USA.

Regional Anesthesia and Pain Medicine
|February 10, 1999
PubMed
Abstract

Insights

Bacterial infection, specifically Staphylococcus aureus, can increase meningeal permeability, potentially affecting drug delivery during epidural procedures. This finding challenges previous explanations for reduced pain relief in infected patients.

Area of Science:

  • Neuroscience
  • Infectious Disease Research
  • Pharmacology

Background:

  • Epidural catheterization carries a risk of bacterial colonization and infection.
  • Reduced analgesia during epidural infections is often observed despite increased opioid doses.
  • Decreased meningeal permeability has been hypothesized as a cause for reduced drug efficacy.

Purpose of the Study:

  • To investigate the impact of Staphylococcus aureus and its toxins on meningeal permeability.
  • To determine if bacterial infection alters the barrier function of the spinal meninges.

Main Methods:

  • Utilized an in vitro diffusion cell model with spinal meninges from M. nemestrina monkeys.
  • Exposed meninges to Staphylococcus aureus toxins A, B, and F, measuring mannitol and sufentanil fluxes.
  • Inoculated diffusion cells with live Staphylococcus aureus to assess sufentanil permeability.

Main Results:

  • Staphylococcus aureus toxin-A increased mannitol flux but not sufentanil flux across the meninges.
  • Toxins B and F did not affect meningeal permeability to mannitol or sufentanil.
  • Live Staphylococcus aureus significantly increased sufentanil permeability by 115%.

Conclusions:

  • Staphylococcus aureus alpha-toxin and live bacteria can enhance meningeal permeability.
  • The observed increase in permeability suggests that decreased drug efficacy during infection is not due to a tighter meningeal barrier.
  • This study provides a new understanding of the interaction between bacterial infection and drug transport in the epidural space.

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