Related Experiment Videos
Effect of tumor necrosis factor-alpha on infection with Salmonella typhimurium in a mouse model
Abstract:
Mice, inoculated with Salmonella typhimurium, either intraperitoneally (i.p.) or intragastrically (i.g.), developed a systemic infection with a high death rate within a few days after inoculation. Pretreatment of the mice with moderate concentrations of i.p. administered TNF-alpha 24 h before the administration of bacteria reduced the establishment of intracellular infection in the intestinal epithelial cells, and development of bacteremia. The mortality rate was reduced, and the survival time was extended by the same treatment. This effect of TNF-alpha was more pronounced against i.g. than against i.p. inoculated bacteria. The effect was dose dependent, thus concentrations above or below the optimal dose had less effect. No synergistic effect was seen if TNF-alpha was given in combination with interferon-gamma. These results indicate, that TNF-alpha may have a physiological effect in the host defence against facultatively intracellular Gram-negative bacteria.
Insights
Tumor necrosis factor-alpha (TNF-alpha) pretreatment protected mice against Salmonella typhimurium infection. This immune modulation reduced bacterial spread and mortality, highlighting TNF-alpha
Area of Science:
- Immunology
- Microbiology
- Infectious Diseases
Background:
- Salmonella typhimurium infection in mice leads to systemic illness and high mortality.
- Intracellular infection and bacteremia are key features of Salmonella typhimurium pathogenesis.
Purpose of the Study:
- To investigate the protective effects of tumor necrosis factor-alpha (TNF-alpha) pretreatment against Salmonella typhimurium infection in mice.
- To determine the influence of TNF-alpha administration route and dosage on protection.
Main Methods:
- Mice were inoculated with Salmonella typhimurium via intraperitoneal (i.p.) or intragastric (i.g.) routes.
- Mice received i.p. administered TNF-alpha 24 hours prior to bacterial inoculation.
- Mortality rates, survival times, and bacterial load were assessed.
Main Results:
- TNF-alpha pretreatment significantly reduced intracellular infection in intestinal cells and subsequent bacteremia.
- Mortality was decreased, and survival time was extended in TNF-alpha treated mice.
- The protective effect was dose-dependent and more effective against i.g. than i.p. inoculation.
Conclusions:
- TNF-alpha plays a physiological role in host defense against facultative intracellular Gram-negative bacteria like Salmonella.
- Modulating TNF-alpha levels could be a therapeutic strategy for bacterial infections.