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Salmonella pathogenesis and immunity in cattle and pigs - OZ0315

Samonellosis is now one of the most important bacterial diseases of man and animals in the U.K. and has implications for human and animal health and welfare. The aim of this study is to characterise further the virulence factors influencing Salmonella pathogenesis and the host response to infection in cattle and pigs. The unique facilities of IAH, Compton will be exploited to study natural host/pathogen interactions at the molecular level. Bovine and porcine ligated ileal loops will be infected with wild-type and defined mutant strains of different Salmonella serotypes and the host cells with which the salmonellas interact will be indentified using immunohistocytochemistry in conjunction with fluorescent and confocal laser microscopy. The method of bacterial translocation from the intestinal mucosa to the systemic oragns will be investigated by cannulation of blood and lymph vessels. The effect of infection on the host will be determined with respect to Salmonella-induced cell death, cytokine production and influx of inflammatory cells. The role of specific genes in enteropathogenesis and systemic dissemination will be characterised. Mutants with altered host-specificity will be identified by signiture-tagged mutagenesis and screened in the above assays . This approach will provide insight into the molecular basis of Salmonella pathogenesis, information which is essential for the design of effective and sustainable control measures.
The research meets MAFF policy requirements on food safety and animal health and welfare. The strategic aims are to safeguard food safety, reduce the impact of bacterial disease and develop effective vaccines which cross-protect against all relevant Salmonella serotypes and reduce the dependance on antibiotics which may lead to the emergence of antibiotic resistant strains.
1. To characterise Salmonella-host cell interactions within intestinal mucosa
2. To identify the mechanism of bacterial translocation from the intestinal lumen to the mesenteric lymph nodes (MLN) and systemic organs.
3. To characterise the host response to intestinal infection and bacterial translocation with respect to production of inflammatory mediators, influx of inflammatory host cells and bacterial-induced death of host cells.
4. Identify mutants with altered host-specificity.
5. To characterise the role of specific bacterial genes in the above processes.
Project Documents
• Final Report : Salmonella Pathogenesis and Immunity in Cattle and Pigs   (79k)
Time-Scale and Cost
From: 1999

To: 2002

Cost: £656,100
Contractor / Funded Organisations
Institute for Animal Health (BBSRC)
Animal Health              
GM Non-Food              
Plants and Animals              
Fields of Study
Animal Health