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Quantifying the Cytotoxicity of Staphylococcus aureus Against Human Polymorphonuclear Leukocytes
12:27

Quantifying the Cytotoxicity of Staphylococcus aureus Against Human Polymorphonuclear Leukocytes

Published on: January 3, 2020

Effect of ciprofloxacin and ofloxacin on human polymorphonuclear leukocyte activity against staphylococci

A Pascual1, L Martínez-Martínez, E J Perea

  • 1Department of Microbiology, School of Medicine, University of Seville, Spain.

Chemotherapy
|January 1, 1989
PubMed

Insights

Ciprofloxacin and ofloxacin did not affect human immune cell killing of staphylococci at low doses. However, at higher concentrations, these antibiotics reduced viable Staphylococcus aureus within immune cells but not Staphylococcus epidermidis.

Area of Science:

  • Microbiology
  • Immunology
  • Pharmacology

Background:

  • Human polymorphonuclear leukocytes (PMNs) are crucial for combating bacterial infections.
  • Staphylococci, including Staphylococcus aureus and Staphylococcus epidermidis, are significant human pathogens.
  • Fluoroquinolones like ciprofloxacin and ofloxacin are widely used antibiotics.

Purpose of the Study:

  • To investigate the impact of ciprofloxacin and ofloxacin on the bactericidal activity of human PMNs against staphylococci.
  • To determine if subinhibitory and minimal inhibitory concentrations of these antibiotics affect PMN-mediated killing of S. aureus and S. epidermidis.

Main Methods:

  • Human PMNs were isolated and exposed to Staphylococcus aureus and Staphylococcus epidermidis.
  • Bacteria-PMN interactions were assessed following exposure to subinhibitory and minimal inhibitory concentrations of ciprofloxacin and ofloxacin.
  • Bacterial viability within PMNs was quantified using colony counts.

Main Results:

  • Subinhibitory concentrations of ciprofloxacin and ofloxacin did not alter PMN uptake or killing of S. aureus and S. epidermidis.
  • At minimal inhibitory concentrations, ciprofloxacin and ofloxacin significantly reduced viable intraphagocytic S. aureus compared to controls.
  • Neither antibiotic demonstrated a significant reduction in viable intraphagocytic S. epidermidis.

Conclusions:

  • Ciprofloxacin and ofloxacin exhibit differential effects on PMN-mediated killing of staphylococcal species.
  • These antibiotics may enhance the clearance of Staphylococcus aureus by PMNs at therapeutic concentrations.
  • The efficacy against Staphylococcus epidermidis within PMNs remains unaffected by ciprofloxacin and ofloxacin.

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