MSc Physiology

"Bugs and the gut: Cross-talk, coercion and subversion"

Dr Barry Campbell

Enteric Gram negative pathogens cause the bulk of the burden of diarrhoea. Enteric fever leads to about 3 million deaths per year. Toxigenic diarrhoeas account for ~20% of identifiable diarrhoeal disease worldwide
 
There have been significant advances in understanding the mechanisms by which enteric bacteria (and their toxins) subvert or coerce host cell processes to inadvertently contribute to pathogenesis and disease outcome. Whereas some pathogens (e.g. Salmonella and Shigella) with an intracellular lifestyle have developed sophisticated strategies to invade and survive in host cells, some pathogens (e.g. enteropathogenic E. coli, EPEC) prevent their own uptake. Both invasion and antiphagocytosis require co-ordinated action of many bacterial effectors on host signalling pathways. A common feature is the modulation of G-proteins involved in cellular signal transduction and re-arrangement of the host cytoskeleton.
 
Our own research is examining a new type of adherent and invasive E. coli (AIEC) associated with the mucosae of patients with inflammatory bowel disease and colon cancer. These strains are commensals in the conventional sense that they lack known markers of pathogenicity (such as invasins and toxins) but they are proinflammatory, adherent and invasive to intestinal epithelial cells.

References


 
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Abstract
 
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Abstract
 
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Abstract
 
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