Current Research
My research is currently focused on the human bacterial pathogen Helicobacter pylori, which is the main cause of stomach ulcers and gastric cancer. I am studying mucosal immunity and inflammation, T-cell subset responses (particularly regulatory T-cells and Th17), development of novel diagnostics, and gastric carcinogenesis. I am interested in how virulence factors (such as the cag pathogenicity island and duodenal ulcer promoting gene A) interact with host cells to provoke a more severe inflammatory response. Apart from associations with gastro-duodenal disease I am interested in the hygiene hypothesis and am exploring the link between some infections (H. pylori and gastro-intestinal parasites) and a reduced risk of allergy and autoimmune disease. Most of our work involves isolating and characterizing immune cells from human gastric tissues and peripheral blood.
Current main projects include
- Characterization of human T-helper subset responses to H. pylori infection.
- The role of regulatory T-cells in modulating H. pylori-induced pathology.
- Discovering immunomodulatory molecules expressed by H. pylori.
- The interaction of H. pylori virulence factors with host in causing inflammation, ulceration and carcinogenesis in the human stomach.
- The effect of dupA- and cagPAI-positive strains of H. pylori on human dendritic cell responses.
- Investigating the link between chronic mucosal infections and reduced risk of allergy and autoimmune disease, via epidemiology, work with samples from patients, and using in vivo models.
The techniques in use in the laboratory include
- Isolation of immune cells from human tissue
- Intracellular staining and flow cytometry
- Real-time qPCR to quantify H. pylori colonization densities from human gastric biopsy tissues
- Real-time RT-qPCR to quantify the expression of pro- and anti-inflammatory genes and markers of Treg activity
- Lymphocyte migration assays, using in vitro cell culture systems and in vivo imaging
- Cloning, expression and purification of bacterial antigens
- Serological analysis for diagnosis of H. pylori infections
- Various cell signalling methods
Past Research
Neisseria meningitidis: Immunity and inflammation, vaccines
Recombinant lactic acid bacteria as vaccine vectors
Mucosal immunology and oral vaccines
DNA vaccines
Immunity to gastrointestinal helminth parasites Trichinella spiralis & Trichuris muris
Host-pathogen interactions.
Diagnostics