Dr Charani Ranasinghe, Molecular Mucosal Vaccine Immunology Group, Department of Immunology, The John Curtin School of Medical Research, ANU.
Three decades have passed since the discovery of HIV/AIDS and there is still no cure for the disease. Unfortunately, systemic vaccines or vaccines delivered into the blood compartment that have induced good immunity in animal models have failed to translate effectively into clinical trials. During our studies into understanding “why” these vaccines have elicited poor immune outcomes in humans, we have found that systemic vaccines induce elevated expression of certain hormone like molecules known as Th2 cytokines that can dampen the “quality” of killer T cell immunity. In contrast, our studies indicate that mucosal vaccination (intranasal) can induce killer T cells of greater “quality” and better protective immunity in animal models. As HIV is a disease of the mucosae, we believe that a vaccine that can induce immunity at these primary sites of infection (genito-rectal and gastro-intestinal tracts) would be of great importance in the fight against HIV. In our laboratory we have now designed a series of novel mucosal vaccines that can induce “high quality” killer T cell immunity. We hope that these vaccins will contribute to a successful HIV vaccine in the near future.