Adhesion, invasion and intracellular replication of Salmonella typhimurium in a murine hepatocyte cell line. Effect of cytokines and LPS on antibacterial activity of hepatocytes

Microb Pathog. 1996 Nov;21(5):319-29. doi: 10.1006/mpat.1996.0065.

Abstract

Elimination of pathogenic microorganisms in the liver may be an important effector mechanism in host defenses. In this paper we describe the adhesion, invasion and multiplication of Salmonella typhimurium in a murine embryonic hepatocyte cell line (ATCC TIB-73). Monolayers of hepatocytes treated with recombinant IFN gamma, IL1 beta, and LPS exhibit antibacterial activity against intracellular Salmonella. The dynamic of the infection process in stimulated vs unstimulated hepatocytes was determined by counting the number of survival bacteria in the cell monolayers at 4 and 28h after gentamicin was added to the infected cells. Salmonella typhimurium is able to adhere, invade and replicate inside the hepatocytes. The maximum number of cell-associated bacteria is approximately 15 bacteria per cell, whereas the invasive capacity of Salmonella is 0.003 bacteria per hepatocyte. Stimulated cultures display antibacterial activity compared to unstimulated controls. The antibacterial activity does not seem to be mediated by nitric oxide (NO) since inhibition of NO production by using NG-Monomethyl-L-Arginine did not revert the antibacterial activity. Also, high amounts of NO induced by adding L-Arginine to the cell cultures did not enhance hepatocyte antibacterial activity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacterial Adhesion
  • Cell Line
  • Colony Count, Microbial
  • Interferon-gamma / pharmacology*
  • Interleukin-1 / pharmacology*
  • Lipopolysaccharides / pharmacology*
  • Liver / cytology
  • Liver / drug effects
  • Liver / immunology*
  • Mice
  • Nitric Oxide Synthase / antagonists & inhibitors
  • Recombinant Proteins
  • Salmonella typhimurium / growth & development
  • Salmonella typhimurium / physiology*
  • Time Factors
  • Tumor Necrosis Factor-alpha / pharmacology*
  • omega-N-Methylarginine / pharmacology

Substances

  • Interleukin-1
  • Lipopolysaccharides
  • Recombinant Proteins
  • Tumor Necrosis Factor-alpha
  • omega-N-Methylarginine
  • Interferon-gamma
  • Nitric Oxide Synthase