Population Dynamics Analysis of Ciprofloxacin-Persistent S. Typhimurium Cells in a Mouse Model for Salmonella

Patrick Kaiser1, Roland R Regoes2, Wolf-Dietrich Hardt3

  • 1Institute of Microbiology, D-BIOL, Eidgenössische Technische Hochschule ETH Zurich, Office HCI G417, Vladimir-Prelog-Weg 4, Zürich, 8093, Switzerland.

Insights

Antibiotics often fail to eradicate bacterial infections. This study reveals tolerant Salmonella Typhimurium cells survive in immune cells, hindering treatment. A new computational method analyzes these persistent bacterial populations.

Area of Science:

  • Microbiology
  • Immunology
  • Computational Biology

Background:

  • Antibiotics exhibit limited efficacy in eradicating bacterial pathogens in vivo.
  • Tolerant bacterial cells, specifically Salmonella Typhimurium (S. Typhimurium), survive within host immune cells like monocytes (classical dendritic cells) during ciprofloxacin therapy.
  • This survival within immune niches contributes to treatment inefficiency.

Purpose of the Study:

  • To analyze the growth characteristics of persistent S. Typhimurium cells that survive antibiotic treatment.
  • To develop and describe a novel population dynamics approach for studying bacterial persistence in vivo.
  • To provide a computational framework for assessing the growth parameters of persistent bacteria.

Main Methods:

  • Development of a population dynamics approach utilizing mixtures of wild-type isogenic tagged strains (WITS).
  • Infection of a mouse model with S. Typhimurium.
  • Computational analysis of WITS data to quantify bacterial populations.
  • Computer simulations to assess the quality of growth parameters for persistent S. Typhimurium.

Main Results:

  • Identification of tolerant S. Typhimurium cells surviving within lymph node monocytes.
  • Characterization of the growth dynamics of these persistent bacterial populations.
  • Validation of a computational model for analyzing bacterial persistence.

Conclusions:

  • The developed WITS and computational modeling approach provides a robust method for studying bacterial persistence.
  • This generic approach can be adapted to investigate persistent pathogens in various organs and with different bacterial species.
  • Understanding the growth characteristics of persistent bacteria is crucial for improving antibiotic therapy efficacy.

Related Concept Videos