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High-throughput Assay to Phenotype Salmonella enterica Typhimurium Association, Invasion, and Replication in Macrophages
11:10

High-throughput Assay to Phenotype Salmonella enterica Typhimurium Association, Invasion, and Replication in Macrophages

Published on: August 11, 2014

Invasion and replication of Salmonella typhimurium in animal cells

L C Gahring1, F Heffron, B B Finlay

  • 1Department of Immunology, Research Institute of Scripps Clinic, La Jolla, California 92037.

Infection and Immunity
|February 1, 1990
PubMed

Insights

Most Salmonella typhimurium mutants avirulent in macrophages showed defects specific to phagocyte survival. These bacterial mutants invaded and replicated normally in nonphagocytic cells but failed to survive within macrophages.

Area of Science:

  • Microbiology
  • Bacterial Pathogenesis
  • Cell Biology

Background:

  • Salmonella typhimurium is a significant human pathogen.
  • Avirulent mutants are valuable tools for studying bacterial virulence factors.
  • Understanding Salmonella survival mechanisms within host cells is crucial for developing effective treatments.

Purpose of the Study:

  • To characterize the adherence, invasion, and replication capabilities of highly avirulent Salmonella typhimurium mutants.
  • To determine the cellular specificity of defects in Salmonella mutants.
  • To identify specific virulence defects in Salmonella typhimurium.

Main Methods:

  • Utilized 81 avirulent Tn10 insertion mutants of Salmonella typhimurium.
  • Assessed mutant survival in murine macrophages (J774 cell line).
  • Evaluated adherence, invasion, and replication in nonphagocytic human colon adenocarcinoma cells (Caco-2).

Main Results:

  • Most mutants exhibited defects specific to survival within professional phagocytes.
  • Mutants invaded and replicated normally in Caco-2 cells but did not survive in J774 macrophages.
  • One mutant showed significantly reduced invasion in both cell types, attributed to decreased adherence.

Conclusions:

  • The study identified Salmonella typhimurium mutants with defects primarily affecting survival in macrophages.
  • These findings highlight the specific challenges Salmonella faces within phagocytic cells.
  • One mutant's defect was linked to reduced bacterial adherence to host cells, impacting invasion efficiency.

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