Intestinal Disease Research
Head: Dr Ted O'Loughlin
Telephone: 9845 3999
Fax: 9845 3970
See also: Gastroenterology in the Hospital's Directory of Services.
The focus of our group has been the the study of epithelial physiology with particular reference to the pathophysiology of infectious diarrhoea. Currently we are investigating microbial epithelial interactions in a cell culture model of E.coli infection utilising non invasive strains, Enteropathogenic and Enterohaemorrhagic E.coli. These organisms adhere to the surface of gut epithelial cells and induce changes in the cell architecture to maintain their niche. This results in major changes in cell physiology some of which are bug induced, others are host defence responses to the presence of pathogenic bacteria.
We are combining our expertise in microbiology and physiology with other groups investigating the cell cytoskeleton. We have discovered novel structures present in the apical membrane of secreting epithelial cells characterised by well organised actin/tropomyosin bundles which co-aggregrate with epithelial chloride channels. Infection reduces chloride secretion and causes marked rearrangements of these structures. We are currently trying to establish the function of these interesting cytoskeletal proteins.
We are also looking to address the role of the cytoskeleton in the transduction of proinflammatory signals which are produced by the epithelial cells in response to infection. We originally hypothesised that the cell deformation induced by the adherent bacterial may in some fashion signal the presence of the pathogen to the cell and initiate a cascade of signals designed to initiate a host inflammatory response to the bacteria. This is a novel concept in gut physiology and initial experiments suggest that our original hypothesis is correct.
The laboratory research is complemented by epidemiological studies of Shiga-toxin producing E.coli infection in the local paediatric population being conducted in collaboration with the Australian Paediatric Surveillance Unit. We have been conducting nationwide surveillance of Haemolytic Uraemic Syndrome over the past 5 years and have generated information about clinical outcomes as well as detailed microbiological data re E.coli strains.
Bell, C., Elliott, E., Wallace, J., Redmond, D., & O'Loughin, E. (2000). Do eicosanoids cause colonic dysfunction in E.coli O157:H7 infection? Gut, 46, 806-812.
Smith, R., Edwards, M., Notaras, E., & O'Loughin, E. (2000). Esophageal motility in brothers with an FG like syndrome. Am.J.Med.Genetics, 91, 185-189.
This document was published on Thursday, 21 February 2002