Respiratory Syncytial Virus Matrix Protein-Host Protein Interactions As Targets For Therapeutics
Funder
National Health and Medical Research Council
Funding Amount
$686,885.00
Summary
Respiratory syncytial virus (RSV) causes more deaths in winter than influenza, being the major cause of viral pneumonia in infants worldwide, and a potent lower respiratory pathogen in the elderly and immunosuppressed adults. The present proposal will apply a range of techniques to search for new inhibitors of viral infection which target host-virus interactions, as the first step towards new generation anti-viral agents to treat RSV infection.
Even in well-resourced countries, the ability to continue treating HIV patients for their lifetime may become unaffordable, which has focused attention on developing a cure for HIV. We have exploited unique insights into a pathway for Tat expression from latent HIV to identify novel compounds that target HIV latency. This project assembles a multidisciplinary team to optimize the lead compounds, and develop novel drug regimens to fast-track into clinical development as a HIV-curative therapy.
Control Of Viral Replication By Non-coding Viral RNA
Funder
National Health and Medical Research Council
Funding Amount
$502,270.00
Summary
In 25 years since identified, HIV-AIDS deaths have exceeded 30 million and 40 million more are now living with HIV. The toll will soon far surpass any other infectious disease epidemic in history, or even military deaths from war in the past century. While effective combination drug therapies are available, multi-drug resistant HIV strains are commonly transmitted, leaving some patients with limited treatment options. New classes of drugs aimed at different steps in virus replication are urgentl ....In 25 years since identified, HIV-AIDS deaths have exceeded 30 million and 40 million more are now living with HIV. The toll will soon far surpass any other infectious disease epidemic in history, or even military deaths from war in the past century. While effective combination drug therapies are available, multi-drug resistant HIV strains are commonly transmitted, leaving some patients with limited treatment options. New classes of drugs aimed at different steps in virus replication are urgently needed. We have discovered that viral RNAs that do not code for protein serve important functions in HIV replication. We will study the molecular mechanisms these non-coding (intron) RNAs previously considered junk use to support of HIV gene expression and assess their potential as drug targets. First, we will investigate the role of these junk RNA loops, or lariat introns, produced in large amounts during the HIV replication cycle. Retroviruses employ RNA splicing to make mRNA for envelope and regulatory accessory genes. The complex alternative RNA splicing pattern of HIV spawns several non-coding lariats, including the lariat-intron that contains much of the removed env coding sequence. We have made the counterintuitive finding that the env-lariat dramatically enhances expression of Env protein. We will examine how this occurs and the involvement of the new class of gene-expression controlling micro-RNAs in this process. We will test for functional activity from the other lariat-introns that are produced by HIV. Second, we will characterise the mRNA-element required for efficient expression of the HIV envelope glycoprotein, Env gp160, which is essential for virus binding and entry during infection. This RNA-element directs the cell protein translation machinery to commence protein synthesis at the start of the Envgp160 rather than at upstream start sites for Vpu and Rev. We will determine how this RNA element works, its structure, and how it might be inactivated.Read moreRead less
Immunopathogenesis Of Varicella Zoster Virus Infection
Funder
National Health and Medical Research Council
Funding Amount
$346,250.00
Summary
Varicella zoster virus (VZV) is a herpesvirus which infects up to 90% of the population. VZV causes chicken pox (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. Shingles affects many elderly i ....Varicella zoster virus (VZV) is a herpesvirus which infects up to 90% of the population. VZV causes chicken pox (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. Shingles affects many elderly individuals and a major complication is prolonged severe pain or post-herpetic neuralgia (PHN), which can be severely debilitating and often requires follow-up medical care for months or even years after the initial attack. Despite its significant impact on the community, little is known about how this virus functions and causes disease. This project aims to improve our understanding of how VZV infection affects specialised human cells in order to provide novel information for the development of therapies aimed at lessening the impact of VZV disease on the community. This project has four components: (1) We will continue studies which have shown that VZV causes programmed cell death (apoptosis) in human skin cells (fibroblasts) but not human nerve cells (neurons). We aim to identify viral genes responsible for the cell-type specific modulation of apoptosis in human neurons and fibroblasts (2) We will examine human sensory ganglia (clusters of human nerve cells) during shingles and determine what immune cells are present and whether neurons are undergoing apoptosis (3) To assess the impact of VZV infection on the ability of specialized immune cells (called dendritic cells) to mature properly (4) We have shown that VZV may actively avoid immune detection by interfering with the function of dendritic cells. We aim to identify the mechanism responsible for the virus interfering with the expression of immune molecules which are essential for our immune system.Read moreRead less
Hepatitis C virus (HCV) and Human immunodeficiency virus (HIV) infect 200 million and 50 million people world-wide, respectively, and there are no preventative vaccines. The work outlined in this fellowship seeks to understand the structure and function of the major surface proteins of these viruses, their ability to be recognised by the immune system and to develop a novel vaccine for the prevention of HCV.
Herpesviruses infect most Australians and cause recurrent ulcers, birth defects and cancer. Infection lasts lifelong, and spreads to close contacts without obvious clinical signs. Thus disease is hard to prevent. However we can learn much from related animal infections. We have shown that both mouse and human herpesviruses enter mice via cells in the nose. Thus human infections might follow the same route. We will define what body defences work here and whether vaccines can prevent infection.
Human ?-herpesviruses persist for life, cause cancers and emerge with particular virulence when the immune system is weak. Vaccination against them is therefore an important health priority. We have shown for a related ?-herpesvirus of mice that live vaccines protect. Antibody seems to play a major role. We will test whether safer, recombinant vaccines are also sufficient to elicit protective antibody. Thus we can establish a viable strategy for preventing virus-induced human cancers.
Viral infections of the gut are one of the most debilitating infections one can suffer from. Noroviruses are the most common causative agents of viral-associated gastroenteritis but unfortunately little is known regarding their biology and pathogenesis. Our study aims to investigate the replication and pathogenesis of a mouse norovirus to shed light on similar aspects relating to human norovirus infection. We aim to understand how virus infection in cells leads to disease symptoms.
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