Molecular Mechanism And Therapeutic Implications Of Prion Disease Strain Types In Sporadic Creutzfeldt Jakob Disease.
Funder
National Health and Medical Research Council
Funding Amount
$345,634.00
Summary
The prion diseases are a group of transmissible, neurodegenerative disorders affecting both humans and animals. The most common form in humans is sporadic Creutzfeldt-Jakob disease (CJD), although acquired (variant CJD) and inherited (familial CJD) forms also exist. Prion diseases are transmissible by inoculation with, or dietary exposure to, infected tissues. The infectious agent, referred to as a prion , has not been conclusively identified. However, a major component of purified prions is an ....The prion diseases are a group of transmissible, neurodegenerative disorders affecting both humans and animals. The most common form in humans is sporadic Creutzfeldt-Jakob disease (CJD), although acquired (variant CJD) and inherited (familial CJD) forms also exist. Prion diseases are transmissible by inoculation with, or dietary exposure to, infected tissues. The infectious agent, referred to as a prion , has not been conclusively identified. However, a major component of purified prions is an abnormal disease associated form of the host prion protein. Differences in the duration of illness and pathology of sporadic CJD suggests that the disease may be caused by different prion strains. The existence of different prion strains may explain the limited clinical success of anti-prion therapeutics modeled in rodent models of prion diseases. In this study a cell-free model of prion propagation will be used to investigate the basis of human prion strains. This assay will also be used to identify and determine whether the therapeutic efficacy of anti-prion compounds is influenced by human prion strain type. This study will represent the first host species and prion strain specific screen of anti-prion therapeutics aimed at developing the best possible model for the identification and development of therapeutics for human prion diseases.Read moreRead less
CHARACTERISATION OF NOVEL PICORNAVIRUS-LIKE VIRUSES IDENTIFIED FROM PATIENTS WITH ACUTE RESPIRATORY INFECTIONS.
Funder
National Health and Medical Research Council
Funding Amount
$366,998.00
Summary
The common cold and serious chest colds are usually due to viral infections, and mostly occur in children. Unfortunately we can only be certain of the virus causing this illness in as little as 15% of cases. We intend to address this lack of research by examining, in detail, a new virus we recently identified in a child with serious respiratory illness that required admission to hospital. Testing by our laboratory suggests that the new virus is related to picornaviruses (which cause some common ....The common cold and serious chest colds are usually due to viral infections, and mostly occur in children. Unfortunately we can only be certain of the virus causing this illness in as little as 15% of cases. We intend to address this lack of research by examining, in detail, a new virus we recently identified in a child with serious respiratory illness that required admission to hospital. Testing by our laboratory suggests that the new virus is related to picornaviruses (which cause some common colds) but seems to be present in children with far more serious illness. Our study plans to more completely identify the new picornavirus-like virus (PLV) using the tools of molecular biology and the expertise of a senior team of Australian scientists and clinicians who have recently made several virus discoveries in Australia, demonstrating that Australian virus research is capable of achieving highly competitive results that benefit our hospitals and especially their young patients. Our studies will develop extremely sensitive tests which rely on the detection of very small amounts of the viral genome. We can use these tests to determine what the whole virus looks like, when it might occur during the year and whether the PLV are found worldwide. Our studies will also produce viral proteins in the laboratory and use these to make new tests for stored blood samples. If a blood sample comes from a patient who has previously been infected by PLV, their blood will contain specific antibodies which we will then be able to detect. We also intend to determine whether some strains of PLV are more or less likely to cause serious illness than others. Improved understanding of these and other viruses minimises the chance of illness spreading within a hospital, helps scientists to decide against which viruses to design vaccines and drugs and aids medical doctors to better identify what once went undiagnosed.Read moreRead less
Hepatitis C virus is a major medical problem in Australia and many other parts of the world. The viruses causes a persistent infection in most infected individuals that results in serious liver disease and liver cancer in a proportion of patients. Treatment is only possible for a small percentage of patients and many patients are infected with viruses which are resistant to the best contemporary treatment regimens. The aim of this project is to develop systems which will result in the assembly o ....Hepatitis C virus is a major medical problem in Australia and many other parts of the world. The viruses causes a persistent infection in most infected individuals that results in serious liver disease and liver cancer in a proportion of patients. Treatment is only possible for a small percentage of patients and many patients are infected with viruses which are resistant to the best contemporary treatment regimens. The aim of this project is to develop systems which will result in the assembly of virus particles which can be used to examine the efficacy of potential antiviral agents, either in the test tube or by infecting an animal model. In particular, we will examine the contribution of a small viral protein, p7, on virus assembly and secretion from the infected cell. Recent data suggests that p7 can function to help release virus from the infected cell and a number of inhibitors of p7 function have been described. We will then use the systems which we develop to determine if these inhibitors can inhibit virus replication in the test tube and in animal models.Read moreRead less
UNDERSTANDING HEPATITIS C VIRUS-SPECIFIC T CELL TOLERANCE
Funder
National Health and Medical Research Council
Funding Amount
$429,710.00
Summary
Most individuals who are infected with hepatitis C virus (HCV) develop a persistent infection that is lifelong and are at risk of developing serious liver disease, including liver cancer. The evidence suggests that an inadequate immune response is responsible for the inability of the patient to resolve the infection, but it is not clear which stage of the immunological cascade might be targeted. In this project, we will test the hypothesis that HCV antigen induce supressor T cells This will have ....Most individuals who are infected with hepatitis C virus (HCV) develop a persistent infection that is lifelong and are at risk of developing serious liver disease, including liver cancer. The evidence suggests that an inadequate immune response is responsible for the inability of the patient to resolve the infection, but it is not clear which stage of the immunological cascade might be targeted. In this project, we will test the hypothesis that HCV antigen induce supressor T cells This will have the effect of inhibiting the immune response and result in the outcome that we currently recognise as persistent HCV infection.Read moreRead less
Use Of Mouse Models To Study Mechanisms Of Pathology In Viral Exacerbations Of COPD
Funder
National Health and Medical Research Council
Funding Amount
$411,960.00
Summary
We want to understand why cigarette smoke exposure worsens respiratory virus infections. People who smoke, or who have smoked in the past, or who are exposed to environmental (passive) smoke, get sicker than nonsmokers when they get a respiratory virus infection, such as a common cold or the flu. This is true for people of all age groups, but we don't know why smoke has this effect. We think it may be because smoke interferes with some aspects of the immune response. A particular focus of our re ....We want to understand why cigarette smoke exposure worsens respiratory virus infections. People who smoke, or who have smoked in the past, or who are exposed to environmental (passive) smoke, get sicker than nonsmokers when they get a respiratory virus infection, such as a common cold or the flu. This is true for people of all age groups, but we don't know why smoke has this effect. We think it may be because smoke interferes with some aspects of the immune response. A particular focus of our research is chronic obstructive pulmonary disease. COPD is a serious lung disease which generally occurs in people who have smoked for many years. However, many COPD patients stopped smoking many years ago. COPD patients are especialy at risk of serious outcomes if they get a respiratory infection (known as an acute COPD exacerbation) and patients with COPD exacerbations use a lot of health care resources. There are no effective drugs to prevent or treat COPD exacerbations. We are currently using a mouse model of smoke exposure and virus infection to do this research, which is a much faster and more ethical approach than using humans in research. We believe that we will get a better understanding of how smoke affects the immune response to infection. This is likely to contribute to the development of better drugs for COPD exacerbations and other types of smoking related lung disease.Read moreRead less
Prophylactic Vaccine To Prevent Cytomegalovirus Disease
Funder
National Health and Medical Research Council
Funding Amount
$436,360.00
Summary
This project is aiming to develop a prophylactic vaccine against a common herpesvirus which has been linked to the birth defects in new born babies and significant morbidity and mortality in transplant patients. In this project we are testing a novel nanoparticle-based vaccine formulation which stimulates the immune system with single injection and the immunity induced is sustained for long-term.
Human immunodeficiency virus type 1 (HIV-1) causes AIDS and, to date, has infected approximately 20 thousand people in Australia and more than 40 million worldwide. People infected with HIV-1 first experience a period of 5-7 years where they remain healthy, ofter assisted by the use of anti-HIV-1 drugs, and this period is referred to as the asymptomatic period. After this period, infected individuals become sick due to their immune system being destroyed, and this is referred to as AIDS. Researc ....Human immunodeficiency virus type 1 (HIV-1) causes AIDS and, to date, has infected approximately 20 thousand people in Australia and more than 40 million worldwide. People infected with HIV-1 first experience a period of 5-7 years where they remain healthy, ofter assisted by the use of anti-HIV-1 drugs, and this period is referred to as the asymptomatic period. After this period, infected individuals become sick due to their immune system being destroyed, and this is referred to as AIDS. Research into how HIV-1 causes AIDS has shown us that the virus changes over time to make itself better able to kill cells of the immune system, by at least 2 mechanisms. The first mechanism, which is the best characterised one, is where the virus changes the way it infects cells, whereby it can infect many more cells in the body by taking advantage of an alternate receptor molecule on the cell called CXCR4. This molecule is very widely expressed on immune cells, and thus the virus can now infect and kill many more cells. However, in about 50% of infected people who eventually get AIDS, the virus does not change this way. The virus instead uses it's original receptor to infect cells, called CCR5. Our preliminary studies, as well as other published reports, suggest that the virus changes itself another way to make it kill immune cells better, without using CXCR4. However, the mechanism by which HIV-1 does this is poorly understood. This proposal aims to better understand this mechanism. We expect to find that, in this group of patients, the Env proteins on the virus change to be able to bind CCR5 more tightly, and thus be able to use fewer molecules of CCR5 to infect cells. We believe that these forms of the virus are now better able to kill immune cells, leading to AIDS. This study will contribute to a greater understanding of how HIV-1 causes AIDS, which is necessary for the development of new drugs to treat HIV-1 infection.Read moreRead less
Influenza remains an important disease and exacts a high toll in both morbidity and mortality each year. This project will identify the carbohydrates that are utilised by influenza virus to initiate infection throughout the body and map how these carbohydrates interact with the key viral surface proteins. This research will provide new insight into the emergence of new influenza virus strains and cross-species pathogenicity.
THE ROLE OF CELL SURFACE GLYCOSAMINOGLYCANS IN FLAVIVIRUS BIOLOGY: VIRUS ENTRY, TROPISM, VIRULENCE, AND ANTIVIRALS
Funder
National Health and Medical Research Council
Funding Amount
$493,764.00
Summary
The flaviviruses are a group of viruses mostly transmitted by the bite of infected mosquitoes or ticks to vertebrate hosts. They have a world-wide distribution and many flaviviruses are important human and veterinary pathogens. Dengue virus is the most important flavivirus in terms of disease frequency, causing >50 million cases of dengue fever, annually, in tropical and subtropical countries. It has been estimated that 2.5 billion people are at risk of dengue virus infection. Japanese enceph ....The flaviviruses are a group of viruses mostly transmitted by the bite of infected mosquitoes or ticks to vertebrate hosts. They have a world-wide distribution and many flaviviruses are important human and veterinary pathogens. Dengue virus is the most important flavivirus in terms of disease frequency, causing >50 million cases of dengue fever, annually, in tropical and subtropical countries. It has been estimated that 2.5 billion people are at risk of dengue virus infection. Japanese encephalitis virus is the most important causative agent of viral encephalitis in humans; >35,000 cases of Japanese encephalitis occur annually, with 30-50% mortality and frequent life-long neurological impairment among survivors. Murray Valley encephalitis virus is endemic in northern Australia where it gives rise, in most years, to a small number of human cases of sometimes fatal encephalitis. Dengue, Japanese encephalitis, and Murray Valley encephalitis viruses are a threat to human health in Australia. There is wide-spread speculation that climate change will affect the pattern of transmission of vector-borne pathogens; accordingly , the population at risk of flavivirus infection in Australia (and world-wide) may dramatically increase in future years. This project investigates the role of sulfated sugar molecules present abundantly on cellular surfaces in the biology of flaviviruses. It will address how the binding ability of medically important flaviviruses to these sulfated sugars impacts on the efficiency of virus entry into diverse cell types and, in turn, on the virus ability to cause disease. Ultimately, we aim to exploit the affinity of flavivirus particles to the sulfated sugar molecules on cellular surfaces; we will select synthetic mimetics of these sulfated sugars that block virus attachment to cells, and thus may identify antiviral compounds that may find application as therapeutic agents against flaviviral disease.Read moreRead less
Molecular Studies Of The Astrocyte Reservoir Of HIV-1 In The Central Nervous System
Funder
National Health and Medical Research Council
Funding Amount
$592,661.00
Summary
HIV infects the brain causing dementia in 10-20% patients. Strategies aimed at eradicating HIV infection fail to take into account CNS infection. Understanding the way in which HIV enters, infects and replicates in the brain is pivotal in development of drugs to prevent brain infection and dementia. Our studies have shown that HIV infection of the brain involves mechanisms distinct to those observed for blood and other organs. This study seeks to clarify such mechanisms.