Novel Generic Vaccine Approaches Applied For The Prevention Of Hepatitis C And Influenza Virus Infections.
Funder
National Health and Medical Research Council
Funding Amount
$392,328.00
Summary
For the induction of good immune responses, antigens should be delivered in several copies on a defined particle. The small envelope protein (HBsAg) encoded by the hepatitis B virus (HBV) has the capacity to self-assemble with host derived lipids into VLPs. HBsAg VLPs are the sole component of one of the most successful vaccines, and clinical trials have shown that they are a successful delivery system for foreign epitopes or protein domains. Hepatitis C virus (HCV) and Influenza viruses are maj ....For the induction of good immune responses, antigens should be delivered in several copies on a defined particle. The small envelope protein (HBsAg) encoded by the hepatitis B virus (HBV) has the capacity to self-assemble with host derived lipids into VLPs. HBsAg VLPs are the sole component of one of the most successful vaccines, and clinical trials have shown that they are a successful delivery system for foreign epitopes or protein domains. Hepatitis C virus (HCV) and Influenza viruses are major human pathogens. HCV has infected 200 million people worldwide, and there is no effective vaccine available. Influenza continues to affect thousands of people each year causing epidemics with severe morbidity and considerable mortality. Current influenza vaccines are mostly inactivated formulations and they exhibit poor immunogenicity in immunological naive persons such as children and in the elderly. The influenza vaccines are not optimal for stimulation of cell-mediated immunity. We propose to use particulate antigens as a delivery platform for influenza and HCV-specific epitopes with the focus to develop approaches to target various HCV and influenza strains, including H5N1 bird influenza. We have successfully produced modified VLPs containing HCV-specific sequences, which are able to induce anti-HCV antibodies with neutralising capacity. We hypothesise that the design of VLPs with an appropriate set of HCV-specific antigens will enhance the neutralising capacity of anti-HCV sera and this may overcome strain specificity. This application will exploit a prototype delivery system to induce antibody and also cellular responses against a variety of HCV- and influenza specific target sequences (epitopes). The outcome of this study will be a prototype multivalent vaccine to a range of HCV- and influenza-specific epitopes. As a delivery system this will be ideal for vaccination against agents that are highly variable.Read moreRead less
A Study Of The Molecular Pathogenesis Of Murray Valley Encephalitis Virus In Mice Using Infectious Clone-derived Virus
Funder
National Health and Medical Research Council
Funding Amount
$194,595.00
Summary
The significance of this project derives primarily from the public health problem posed by epidemics of Murray Valley encephalitis in Australia and, more importantly, by the very much larger and more frequent epidemics of Japanese encephalitis in southeast Asia. Reported case fatality rates of Murray Valley encephalitis and of Japanese encephalitis range from 20 to 40%. Rates of neurological sequelae (motor deficits, mental retardation, convulsions, memory loss) are high among survivors and impo ....The significance of this project derives primarily from the public health problem posed by epidemics of Murray Valley encephalitis in Australia and, more importantly, by the very much larger and more frequent epidemics of Japanese encephalitis in southeast Asia. Reported case fatality rates of Murray Valley encephalitis and of Japanese encephalitis range from 20 to 40%. Rates of neurological sequelae (motor deficits, mental retardation, convulsions, memory loss) are high among survivors and impose a considerable burden on affected individuals and on community health and rehabilitation services. Currently there are no effective treatments, other than supportive measures, available for acute flavivirus encephalitis. The research outlined in this grant application is designed to understand the complex interaction between a pathogenic virus and it's mammalian host at the molecular, cellular and whole animal level. To achieve this aim, we have developed an infectious cDNA clone of Murray Valley encephalitis virus, allowing us to create genetically defined attenuated viruses containing single or limited amino acid differences from the virulent wild-type virus. This research will allow us to achieve a comprehensive understanding of how single or limited nucleotide changes in the genomes of laboratory-derived mutants result in attenuation of virulence in a mammalian host . This research has important implications for the development of genetically defined, live-attenuated flavivirus vaccines engineered from infectious cDNA clones. We have recently shown that the pathogenesis of Murray Valley encephalitis in mice results, in part, from host inflammatory responses. Thus, we plan to rigorously analyze the inflammatory responses to MVE infection in mice and to assess the ability of several anti-inflammatory agents to alleviate the clinical manifestations of acute Murray Valley encephalitis or it's neurological sequelae in mice.Read moreRead less
Host Determinants Of Hepatitis C-associated Liver Disease
Funder
National Health and Medical Research Council
Funding Amount
$610,376.00
Summary
Hepatitis C virus (HCV) infection is a major cause of liver disease and associated deaths in Australia. HCV infection leads to progressive liver failure and may be associated with the development of liver cancer. Currently there are an estimated 220,000 people in Australia living with HCV infection, and by 2020 it is estimated that this number will treble. There is now considerable evidence to indicate that the effect of HCV on the liver is due to ongoing immune activity and the build up of fat ....Hepatitis C virus (HCV) infection is a major cause of liver disease and associated deaths in Australia. HCV infection leads to progressive liver failure and may be associated with the development of liver cancer. Currently there are an estimated 220,000 people in Australia living with HCV infection, and by 2020 it is estimated that this number will treble. There is now considerable evidence to indicate that the effect of HCV on the liver is due to ongoing immune activity and the build up of fat (steatosis) in the liver. This results in the production of biochemical products that lead to tissue damage and to eventual destruction of the liver. Further evidence has recently emerged to suggest that the susceptibility to, and outcome of HCV infection may be influenced by genetic variation in the infected population. The chief investigators on this project have established the best characterised clinical cohort of HCV infected persons worldwide. Further, they have developed considerable expertise in the field of genetics, i.e. the analysis of genes that influence the host's response to an illness. Using this information and expertise, we propose in the present study to analyse in detail the host genetic factors that contribute to variations in the response to HCV, and its correlation with HCV-associated liver damage. This data could allow the development of better patient care strategies and the design of novel therapeutics.Read moreRead less
I am a molecular and cellular biologist with particular interest in understanding the regulation of DNA damage surveillance pathway and its role in the maintenance of genome stability.
Evaluation Of Naturally Occurring Resistance To Direct Acting Antiviral Drugs (DAAs) In Individuals With Acute Hepatitis C Infection
Funder
National Health and Medical Research Council
Funding Amount
$333,778.00
Summary
Hepatitis C therapy in the future is likely to involve the use of Directly Acting Antivirals, which offer a better chance of treatment success and shorter treatment courses. The downside to these new agents is the possible development of drug resistance. Studies suggest that drug resistant strains may already exist in some individuals prior to treatment. This study plans to use sensitive methods to examine how common drug resistant strains are in untreated individuals with acute hepatitis C.
The renewal of my Practitioner Fellowship will continue to facilitate an expanding program of epidemiological and clinical research in viral hepatitis, with a primary focus on hepatitis C. New directions will include development of international clinical cohort and trials networks, particularly to characterise the natural history of early hepatitis C infection and evaluate hepatitis C therapuetic strategies for injecting drug users.