Mechanisms By Which Varicella Zoster Virus And Herpes Simplex Virus Control Host Functions To Enhance Pathogenesis
Funder
National Health and Medical Research Council
Funding Amount
$631,999.00
Summary
Varicella Zoster Virus and Herpes Simplex Virus are alpha-herpesviruses that cause diseases in a majority of the human population. This proposal will explore issues fundamental to disease and pathogenesis of these two closely related herpesviruses, focusing on how these viruses can control host function. In particular, we will define the interactions between these viruses and the natural killer (NK) cell response.
Current anti-HIV therapies can't cure HIV because HIV remains silent(latent) in long-lived cells. The HIV life cycle and virus production is linked to activation of the host cell, which is regulated by dendritic cells. This grant will explore how the factors controlling T cell activation and proliferation control virus expression and latency. By understanding how latent infection is established and maintained, these studies will potentially identify new ways to eliminate HIV infection.
The Role Of Paramyxovirus P Protein Subcellular Trafficking In Virus Pathogenicity And Antagonism Of Host Interferon Responses
Funder
National Health and Medical Research Council
Funding Amount
$78,491.00
Summary
Emerging zoonotic viruses pose a major health threat worldwide, highlighted by recent outbreaks of viruses such as Nipah and Hendra via interspecies invasion to infect humans. A major barrier to interspecies infection is the innate immune response, which viruses must evolve to combat before successful infection can occur. We aim to examine in detail the mechanisms underlying immune evasion of such viruses, with the ultimate goal of discovering novel targets for therapeutics to viral infection.
Defining The Molecular Mechanisms Of Lyssavirus Replication And Immune Evasion: The P Protein Axis
Funder
National Health and Medical Research Council
Funding Amount
$900,995.00
Summary
Lyssaviruses such as rabies virus (RABV) and Australian bat lyssavirus cause rabies disease, which has the highest case-fatality rate of known infectious diseases, causing >60,000 human deaths/year. Critical to this is a protein produced by the virus that is important for both viral growth and evasion of the host's immune defences. This project aims to understand the molecular mechanisms underlying these processes, which may lead to new approaches to combat currently incurable viral diseases.
Molecular Characterisation Of Host Cell Targets Of Human Pathogenic Viruses And Evaluating Their Potential As Novel Therapeutic Targets.
Funder
National Health and Medical Research Council
Funding Amount
$307,946.00
Summary
There are currently no therapeutics to treat victims of Hendra, Nipah or Rabies virus infections, which account for > 50,000 deaths/yr worldwide. Through not fully understood mechanisms, these viruses affect the functions of specific cellular proteins in order to inhibit the host immune system, a process essential to their pathogenicity. We aim to characterise the mechanisms underlying viral inhibition of host immunity and evaluate their potential as novel targets to develop urgently needed t ....There are currently no therapeutics to treat victims of Hendra, Nipah or Rabies virus infections, which account for > 50,000 deaths/yr worldwide. Through not fully understood mechanisms, these viruses affect the functions of specific cellular proteins in order to inhibit the host immune system, a process essential to their pathogenicity. We aim to characterise the mechanisms underlying viral inhibition of host immunity and evaluate their potential as novel targets to develop urgently needed therapeutics against these deadly pathogens.Read moreRead less
Rotavirus is the main cause of severe diarrhoea in children worldwide. In this project, we aim to understand the nature of the first-line immune response to rotavirus in the gut, and elucidate how RV counteracts this response to promote infection. These studies will increase our understanding of how rotavirus causes disease, and facilitate the choice of rotavirus targets for drug development and improved vaccines.
Discovery Of A Novel Immune Evasion Strategy Employed By Mosquito Borne Viruses To Suppress Antiviral Immune Responses
Funder
National Health and Medical Research Council
Funding Amount
$418,642.00
Summary
The transition from mosquitoes, ticks, or other invertebrate vectors to the human hosts represents a crucial step in the successful establishment of arthropod borne viruses (arboviruses). The incidence of arbovirus infections such as dengue virus, West Nile virus, Ross River virus is increasing at an alarming rate in various parts of the world. In addition, the emergence of new viruses resulting in significant mortality in the population is of utmost concern. Vaccines for many of these viruses r ....The transition from mosquitoes, ticks, or other invertebrate vectors to the human hosts represents a crucial step in the successful establishment of arthropod borne viruses (arboviruses). The incidence of arbovirus infections such as dengue virus, West Nile virus, Ross River virus is increasing at an alarming rate in various parts of the world. In addition, the emergence of new viruses resulting in significant mortality in the population is of utmost concern. Vaccines for many of these viruses remain elusive. One factor that contributes to this is the ability of viruses to develop ingenious strategies to avoid or suppress the host defence systems, which enable its successful establishment in the host. Understanding how viruses evade-suppress host defence machinery will certainly enhance and improve our approaches to fight them. For the first time internationally we have discovered a new and novel pathway employed by arboviruses to suppress antiviral immune responses in the host. We have discovered that naturally occurring carbohydrates on viruses derived from mosquito cells, would influence these virus s ability to evade-suppress host antiviral proteins such as interferons. This may be a general effect of arboviruses or may even extend to other viruses , which include a number of deadly pathogens (HIV, Influenza). This research has the potential to significantly expand our understanding of how these viruses establish infection and cause disease. Also this discovery has broader implications for understanding inflammatory processes and their regulation.Read moreRead less
Characterization Of Neutralizing Antibody Responses In HCV Infected Individuals.
Funder
National Health and Medical Research Council
Funding Amount
$478,076.00
Summary
Hepatitis C virus is a major human pathogen infecting 200 million people world-wide. Currently, there is no vaccine to prevent infection and treatment regimes are only partially effective. IInitial HCV infection is frequently asymptomatic and 30% of people spontaneously clear the virus. The remaining 70% of people develop a life-long chronic infection that causes progressive liver disease, cirrhosis and in some cases liver cancer. The reason why some people are able to clear virus has been attri ....Hepatitis C virus is a major human pathogen infecting 200 million people world-wide. Currently, there is no vaccine to prevent infection and treatment regimes are only partially effective. IInitial HCV infection is frequently asymptomatic and 30% of people spontaneously clear the virus. The remaining 70% of people develop a life-long chronic infection that causes progressive liver disease, cirrhosis and in some cases liver cancer. The reason why some people are able to clear virus has been attributed to the development of a strong cellular immune response and antibody is belived to play a monir role in achieving viral clearance. However, measurememnt of antibody responses in HCV infected pateints is routinely performed using conventional diagnostic tests that do not measure antibody that can help neutralize and clear virus. We have developed an assay that accurately measures the level of NAb in patient sera. We have found that chronically infected patients have broadly reactive neutralizing antibodies but that patients who clear virus, naturally or through treatment do not have broadly reactive neutralizing antibodies. Possibly explaining this phenomenon is that early during infection, antibody is frequently specific only to the infecting virus therefore to detect neutralizing antibodies, homologous viral sequences must be examined. In addition, we have found evidence that HCV can evade neutralzing antibodies through masking of sites to which antibodies bind. We propose to explore whether acutely infected patients develop NAb to autologous viral sequences, and how do these viral sequences and the antibody titre change throughout the course of infection and treatment. We also plan to determine the mechanism of neutralization resistance through the use of mutagenesis of resistant HCV glycoproteins. These studies are aimed at gaining a thorough understanding of the true role of antibody in HCV infection and its influence on viral evolution.Read moreRead less
The Role Of The Interaction Of The CMV M11 Immune Evasion Molecule With CD44 In Viral Pathogenesis
Funder
National Health and Medical Research Council
Funding Amount
$457,500.00
Summary
Herpesviruses can cause infections that persist for the lifetime of the host. They have evolved many mechanisms to elude the host's immune response that would otherwise eliminate them. One memberof the herpesvirus family that is particularly adept at avoiding host immunity is cytomegalovirus. This virus, while not causing symptoms in healthy individuals, is a significant cause of disease and mortality in individuals with suppressed immune systems such as transplant and AIDS patients, and in the ....Herpesviruses can cause infections that persist for the lifetime of the host. They have evolved many mechanisms to elude the host's immune response that would otherwise eliminate them. One memberof the herpesvirus family that is particularly adept at avoiding host immunity is cytomegalovirus. This virus, while not causing symptoms in healthy individuals, is a significant cause of disease and mortality in individuals with suppressed immune systems such as transplant and AIDS patients, and in the fetus which has a poorly developed immune system. In the current project we will explore at a molecular level how a virus-encoded molecule called m11 interferes with the functions of a cellular receptor called CD44 that has a range of cell functions including cell migration, activation and proliferation and signal transduction. The interaction of m11 with CD44 modifies cell migration and is likely to affect cell activation. Defining how m11 mediates its affects will allow us to define strategies to develop potential antiviral therapies. As CD44 is also involed in contributing to a range of diseases where inappropriate inflammation develops it may be that m11, or derivatives of it, could be harnessed to ameliorate these inflammatory diseases.Read moreRead less