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Immunological aspects of new quinolones

I Shalit1

  • 1Infectious Disease Unit, Tel-Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Israel.

European Journal of Clinical Microbiology & Infectious Diseases : Official Publication of the European Society of Clinical Microbiology
|April 1, 1991
PubMed

Insights

New quinolone antibiotics generally do not affect immune cells at therapeutic doses. However, some immune functions, like cytokine production, can be enhanced or inhibited depending on drug concentration and study conditions.

Area of Science:

  • Immunopharmacology
  • Microbiology
  • Cell Biology

Background:

  • The immunomodulatory effects of new quinolones are primarily investigated in vitro.
  • Existing studies present conflicting results due to methodological variations.

Purpose of the Study:

  • To synthesize findings on the impact of new quinolones on the immune system.
  • To evaluate both in vitro and in vivo immunomodulatory effects.

Main Methods:

  • In vitro assays assessing immune cell functions (phagocytosis, proliferation, cytokine production).
  • In vivo studies in experimental animals.
  • Analysis of clinical relevance of observed effects.

Main Results:

  • Clinically relevant quinolone concentrations show minimal direct impact on most immune parameters.
  • Enhanced production of certain cytokines (IL-1, IL-2) and colony-stimulating factors observed at achievable concentrations.
  • Inhibition of immune functions occurs at high in vitro concentrations (>50 µg/ml).
  • In vivo studies indicate immune suppression only at very high dosages; therapeutic doses generally show no measurable alterations.

Conclusions:

  • New quinolones exhibit minimal immunomodulatory effects at therapeutic concentrations.
  • Further investigation is warranted for observed stimulatory effects, particularly in neutropenic patients.
  • Ciprofloxacin's potential stimulatory effect on myeloid progenitor cells requires additional research.

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