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Updated: Oct 13, 2026
Chronic Salmonella Infected Mouse Model
Published on: May 31, 2010
Comparative histopathology in mouse typhoid among genetically diverse mice
1Department of Microbiology and Immunology, Medical College of Virginia, Virginia Commonwealth University, Richmond 23298-0678, USA.
Abstract:
Genetically resistant CBA and A/J mice and susceptible BALB/c and C57BL/6 mice were challenged with either an identical infective dose or a minimal lethal dose of Salmonella typhimurium. The histopathological progression of the disease was examined in tissue sections prepared by the JB-4 Plus resin embedding method and compared between the resistant and susceptible mice. In a fatal disease, the lesions in both animal hosts began with focal abscesses within the first three days post infection. Mononuclear cell infiltration started by day 4 and transformed the lesions into granulomata. Well-formed granulomata were evident by day 7 and persisted in sublethally infected resistant mice. Massive bacterial proliferation and extensive tissue degeneration marked the terminal stage of a lethal challenge. There were no distinguishable features that would identify the tissue response to infection in a resistant host from a susceptible one, except that the lesions in the sublethally infected resistant mice advanced slower and were discrete and self-limiting.
Insights
Resistant and susceptible mice infected with Salmonella typhimurium showed similar initial lesions. However, resistant mice developed self-limiting granulomata, while susceptible mice experienced severe tissue damage.
Area of Science:
- Immunology
- Pathology
- Microbiology
Background:
- Salmonella typhimurium infection elicits varied host responses based on genetic susceptibility.
- Understanding the histopathological differences between resistant and susceptible hosts is crucial for disease management.
Purpose of the Study:
- To compare the histopathological progression of Salmonella typhimurium infection in genetically resistant and susceptible mouse strains.
- To identify distinct tissue responses that differentiate resistant from susceptible hosts.
Main Methods:
- Genetically resistant (CBA, A/J) and susceptible (BALB/c, C57BL/6) mice were infected with Salmonella typhimurium.
- Histopathological examination of tissue sections using JB-4 Plus resin embedding.
- Comparison of lesion development and progression between mouse groups.
Main Results:
- Initial lesions (focal abscesses) appeared within three days in both resistant and susceptible mice.
- Mononuclear cell infiltration led to granuloma formation by day 7.
- Resistant mice, when sublethally infected, developed discrete, self-limiting granulomata.
- Lethal infections in susceptible mice showed massive bacterial proliferation and extensive tissue degeneration.
Conclusions:
- Histopathological features of Salmonella typhimurium infection are initially similar in resistant and susceptible mice.
- The key difference lies in the ability of resistant hosts to contain and resolve lesions, forming self-limiting granulomata.
- Lesion progression is slower and more contained in sublethally infected resistant mice.
