Pathogenesis Of Persistent Human Virus Infections Of Global Significance
Funder
National Health and Medical Research Council
Funding Amount
$6,571,328.00
Summary
The study will investigate why humans cannot eradicate particular viruses (HIV-AIDS, cytomegalovirus and herpes simplex virus), the long term effects of these viruses and ways to improve control. Current treatments can only partly suppress the levels of these viruses, because they persist in certain parts of the body called reservoirs, only to resurge later causing disease. Thus, the overall aim of the research program is to discover the mechanisms by which these viruses are able to successfully ....The study will investigate why humans cannot eradicate particular viruses (HIV-AIDS, cytomegalovirus and herpes simplex virus), the long term effects of these viruses and ways to improve control. Current treatments can only partly suppress the levels of these viruses, because they persist in certain parts of the body called reservoirs, only to resurge later causing disease. Thus, the overall aim of the research program is to discover the mechanisms by which these viruses are able to successfully persist within reservoirs in the human body. The research program brings together a group of 6 leading scientists and clinicians located at 3 sites in 2 Australian cities. The team is comprised of experts in the study of HIV-AIDS, cytomegalovirus and herpes simplex virus who will combine their knowledge and expertise to speed up the process of research on these viruses that are of major health importance. Studies will also utilise a number of cutting edge technologies that now make it possible to much more rapidly and precisely determine how viruses cause disease. Advances in our understanding of how viruses persist may form the basis for treatments aimed at controlling persistent infections and the serious diseases caused by these viruses.Read moreRead less
Molecular Mechanisms Of Varicella Zoster Virus Interactions With Key Target Cells
Funder
National Health and Medical Research Council
Funding Amount
$421,650.00
Summary
Varicella zoster virus (VZV) is a herpesvirus which infects up to 90% of the population. VZV causes chickenpox (varicella) predominantly in childhood and shingles (herpes zoster) in middle to old age people. Whilst VZV usually causes relatively mild disease in healthy individuals, VZV still causes significant morbidity in children and adults. VZV causes life-threatening disease in immunocompromised individuals such as patients who are elderly or have HIV disease . Herpes zoster affects many eder ....Varicella zoster virus (VZV) is a herpesvirus which infects up to 90% of the population. VZV causes chickenpox (varicella) predominantly in childhood and shingles (herpes zoster) in middle to old age people. Whilst VZV usually causes relatively mild disease in healthy individuals, VZV still causes significant morbidity in children and adults. VZV causes life-threatening disease in immunocompromised individuals such as patients who are elderly or have HIV disease . Herpes zoster affects many ederly individuals and a major complication is prolonged severe pain or post-herpetic neuralgia (PHN), both severely debilitating and which often requires follow-up medical care for months or years after the initial attack. Despite its significant impact on the community, little is known about the molecular details of how this virus functions. This project aims to improve our understanding of how VZV infection affects specialised human cells in order to make further advances in antiviral therapies as well improve vaccine design for the treatment or prevention of VZV disease and the crippling complication of PHN. This project has four components: (1) We will continue studies which have shown that VZV may actively avoid detection by the immune system. We aim to identify the mechanism and viral genes responsible for interfering with the expression of molecules which are essential for our immune system. (2) We will determine whether VZV infection of specialised immune cells (called dendritic cells) will affect their ability to function and interact with other immune cells (called T cells). (3) We will examine how VZV interacts in human nerve cells (neurons) and whether infected neurons undergo specially programmed cell death (apoptosis). (4) We will examine how different human cells change when they are infected with VZV. A new and exciting technology called DNA microarray now makes it possible to examine the expression of many thousands of genes in one experiment.Read moreRead less
Understanding HIV Resistance To Entry Inhibitors To Advance The Development Of Novel Antivirals
Funder
National Health and Medical Research Council
Funding Amount
$877,585.00
Summary
We cannot afford to be complacent in the search for improved anti HIV drugs for 2 principal reasons; First, worldwide a staggering 66% of infected individuals who need treatment are still unable to access therapy; and Second, the main reason why most treated patients are now living longer and more healthy lives is because we have never stopped developing newer therapies to provide options for patients. In this study we will develop and test newer drugs that block HIV infection of cells.
Norovirus Infection At The Stress Granule-PKR-p-elF2α Axis
Funder
National Health and Medical Research Council
Funding Amount
$505,967.00
Summary
This project application will aim to investigate and understand how viruses that cause vomiting and diarrhoea are able to infect, proliferate and spread within the human body. It aims to address how viruses are able to avoid and replicate in the presence of an effective immune response. We have evidence showing that Noroviruses are able to exploit certain antiviral proteins to paradoxically aid in virus replication and survival.
The Mechanism Of HSV-1 Transport In Sensory Axons And Its Unique Assembly At The Axon Terminus
Funder
National Health and Medical Research Council
Funding Amount
$670,284.00
Summary
Herpes simplex viruses 1 and 2 cause common diseases such as genital herpes and, occasionally, neonatal deaths and encephalitis and predisposes to HIV infection. New antiviral strategies are required for resistant viruses for control. These aims will be facilitated by understanding how HSV is transported down nerves and across into skin. In this study, we will define how a key viral protein plays a major role in assembly of the virus at the tip of the nerve before it enters skin.
Analysis Of Viral And Cellular Gene Expression During Human Cytomegalovirus Latent Infection Of Hematopoietic Cells
Funder
National Health and Medical Research Council
Funding Amount
$407,545.00
Summary
Human cytomegalovirus (HCMV) is a herpesvirus which infects a majority of the population. HCMV is a significant cause of serious, life-threatening disease in neonates and in people who are immunosuppressed. Transplant recipients such as bone marrow, kidney and heart transplant patients are particularly at risk of developing HCMV disease. Like other herpesviruses, after initial infection HCMV can establish a life-long latent infection. During latency, the virus remains dormant in the human body a ....Human cytomegalovirus (HCMV) is a herpesvirus which infects a majority of the population. HCMV is a significant cause of serious, life-threatening disease in neonates and in people who are immunosuppressed. Transplant recipients such as bone marrow, kidney and heart transplant patients are particularly at risk of developing HCMV disease. Like other herpesviruses, after initial infection HCMV can establish a life-long latent infection. During latency, the virus remains dormant in the human body and no infectious virus is made. However, when conditions are right the virus can awaken (ie reactivate) from its latent state, producing new infectious virus and disease. It is in immunosuppressed individuals such as transplant patients that viral latency and reactivation are of most medical concern, yet viral latency remains very poorly understood. This project has three major components. Firstly, we aim to continue studies which are defining what viral genes are active (ie expressed) during latent infection. Identification of these genes and determination of how they function may have profound implications to our understanding of latency. Secondly, we will examine how human cells are affected when they become latently infected. A new and exciting technology called DNA microarray now makes it possible to examine the expression of many thousands of genes in a single experiment. For the first time, we will be able to determine how the cell changes during latency and reactivation. The study of viral and cellular gene expression during latency may contribute to the development of drugs which interfere with the viruses ability to become latent or reactivate. Thirdly, we have preliminary results which suggest that latent HCMV may actively avoid detection by the immune system. In this project we also aim to determine the mechanism by which the virus interferes with the expression of molecules which are an essential component of our immune system.Read moreRead less
A NOVEL MOUSE MODEL TO INVESTIGATE THE MECHANISMS OF VIRUS-INDUCED ARTHRITIS
Funder
National Health and Medical Research Council
Funding Amount
$336,000.00
Summary
We have developed a novel animal model by which to study arthritic disease caused by insect-transmitted viruses known as arboviruses. The existence of this model and novel reagents provides an excellent opportunity to further explore the basic mechanisms of infectious disease in a complete functioning animal, rather than specific cultured cells. The study will use modern approaches in molecular and cellular biology to achieve this goal. The production by our immune systems of soluble mediators ( ....We have developed a novel animal model by which to study arthritic disease caused by insect-transmitted viruses known as arboviruses. The existence of this model and novel reagents provides an excellent opportunity to further explore the basic mechanisms of infectious disease in a complete functioning animal, rather than specific cultured cells. The study will use modern approaches in molecular and cellular biology to achieve this goal. The production by our immune systems of soluble mediators (cytokines-chemokines) and antibodies is an overwhelming positive aspect of our physiological response to infection by microbes. Protection from disease by these immune compounds can happen naturally, or the body's ability to produce these factors can be exploited to our benefit via the administration of vaccines. However, these factors can also be detrimental to the host contributing to severe disease. For instance, work performed almost 40 years ago showed for the first time that under particular conditions, antibodies against viruses can enhance infection, instead of inhibiting infection as normally seen. In the intervening years work by scientists all over the world has associated antibody-dependent enhancement (ADE) of infection to many types of viruses; ADE is even thought to be a risk factor to serious disease with dengue virus, and has been shown in vitro for the AIDS virus and Ebola virus. We have recently discovered a molecular mechanism which explains how antibody enhances viral infection in vitro. In studies on immune cells infected with Ross River Virus (RRV) we found that infection helped by antibody resulted in the specific disruption to the production of cellular chemicals which are toxic to viruses. Are these mechanisms of antibody-enhanced infection also found in animals? Will such mode of infection cause enhanced disease and tissue pathology (arthritis) in animals?Read moreRead less
The balance between cellular survival and death must be tightly regulated. Cells respond to viral infection by self-destructing, thus limiting viral spread to other cells. Viruses have evolved ways to subvert this defensive cell suicide. This project will define and characterise viral factors that maintain host cell survival during infection. These may be targets for the development of new anti-viral therapies and vaccines.
Dissemination And Virulence Properties Of The She Pathogenicity Island Of Shigella Flexneri.
Funder
National Health and Medical Research Council
Funding Amount
$110,625.00
Summary
Bacterial species belonging to the genus Shigella are responsible for intestinal diseases ranging from mild diarrhoea to life threatening bacillary dysentery. Such diseases kill over a million people, mainly infants in developing countries, every year and lead to serious morbidity and mortality even in industrialised countries with well developed health care systems. In many cases the virulence of Shigella species is augmented by large fragments of DNA, called pathogenicity islands, that carry g ....Bacterial species belonging to the genus Shigella are responsible for intestinal diseases ranging from mild diarrhoea to life threatening bacillary dysentery. Such diseases kill over a million people, mainly infants in developing countries, every year and lead to serious morbidity and mortality even in industrialised countries with well developed health care systems. In many cases the virulence of Shigella species is augmented by large fragments of DNA, called pathogenicity islands, that carry genes which contribute to the development of disease (pathogenesis) in humans. Pathogenicity islands are important genetic elements which appear to spread independantly throughout bacterial populations and therefore contribute to the emergence of new virulence traits in bacteria. Recently, we identified two related pathogenicity islands carried by both Shigella flexneri and other species of the genus Shigella. The two pathogenicity islands belong to a unique class of genetic elements found in Shigella species and virulent strains of the intestinal bacterium E. coli. Our current study is aimed at (1) understanding the mechanisms by which one of these islands, the she pathogenicity island, spreads from one bacterial strain to another to introduce disease-producing or virulence genes to new bacteria and (2) to study how the sigA virulence gene, carried on the she pathogenicity island, contributes to disease development in humans. We know that sigA encodes a protein toxin which contributes to the loss of fluid from the intestines of rabbits that have been experimentally infected with Shigella flexneri. We propose to study the structure and function of the SigA protein to determine how it interacts with tissues to produce a pathological state. Such studies will enhance our understanding of the process of disease development and contribute to the investigation and assessment of new strategies for therapeutic intervention.Read moreRead less