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
Role Of The Hepatitis C Virus Glycoprotein E2 Variable Regions In Viral Entry And Antibody Mediated Neutralization.
Funder
National Health and Medical Research Council
Funding Amount
$542,462.00
Summary
The first stage of Hepatitis C Virus replication involves attaching to liver cells. This study is aimed at understanding how the virus attaches to liver cells and how antibodies raised during infection, block this interaction. In addition, this study aims to examine how the virus modulates its structure to evade the immne system, allowing the virus to establish chronic infections. The results of this study will guide future vaccine design for HCV.
Investigation Of The Roles Of TNFa-related Apoptosis-inducing Ligand, TRAIL, In The Immune System.
Funder
National Health and Medical Research Council
Funding Amount
$436,980.00
Summary
TRAIL, is a newly described member of the tumour necrosis factor (TNF)-family of cytokines, which can kill a wide range of tumour cells, and virus infected cells, but not most normal cells. TRAIL has proven to be safe when administered to normal, tumour bearing, and virally-infected mice, and causes no detectable side-effects in these animals. As such it holds huge potential and is being widely investigated for use as a new anti-cancer therapy. Despite these findings, little is known about the t ....TRAIL, is a newly described member of the tumour necrosis factor (TNF)-family of cytokines, which can kill a wide range of tumour cells, and virus infected cells, but not most normal cells. TRAIL has proven to be safe when administered to normal, tumour bearing, and virally-infected mice, and causes no detectable side-effects in these animals. As such it holds huge potential and is being widely investigated for use as a new anti-cancer therapy. Despite these findings, little is known about the true physiological role of TRAIL in vivo. To define the normal roles of TRAIL, CIA has been characterising TRAIL gene knock-out mice. These studies have confirmed that TRAIL contributes to control of tumours in vivo, and in early events during anti-viral responses. However, these studies have also revealed novel roles for TRAIL in T cell biology, and B cell memory. Understanding how TRAIL contributes to these processes, will shed significant light on the potential of TRAIL to be used as a therapeutic agent for humans with lymphoproliferative disease, for illiciting better long-lived antibody responses such as after vaccination, and as an anti-viral reagent in immunocompromised individuals during virus infection.Read moreRead less
Postviral Wheezing In Childhood: Disregulation Of Airway Tone?
Funder
National Health and Medical Research Council
Funding Amount
$577,040.00
Summary
Asthma is a very common childhood condition that is becoming increasingly more common. Wheezing is common in infants and young children following viral infections and is often thought of as the first manifestation of asthma. However, many children and infants who wheeze with viral infections appear to grow out of asthma in their teenage years. Asthma that persists into adult life is usually associated with allergies to common environmental allergens, such as house dust mite and grass pollens. Ho ....Asthma is a very common childhood condition that is becoming increasingly more common. Wheezing is common in infants and young children following viral infections and is often thought of as the first manifestation of asthma. However, many children and infants who wheeze with viral infections appear to grow out of asthma in their teenage years. Asthma that persists into adult life is usually associated with allergies to common environmental allergens, such as house dust mite and grass pollens. However, many infants who wheeze with viral infections, especially in the first year of life, do not develop allergies in later life, raising the possibility that they did not have the same type of asthma as those whose symptoms persist. This project will study the effects of viral infections on lung function to determine whether particular types of virus can have detrimental effects of lung function lasting for years. We will also examine whether the age at which the infection occurs and the severity of the infection influence the long-term outcome. The project involves studying infants during the recovery phase of respiratory viral infections, older children years after documented infections and experimental animal models that have been infected under controlled conditions. By determining whether respiratory viral infections can have long-term effects on lung function that can mimic asthma, we will advance our understanding of how asthma develops. In addition, specific treatment and preventative strategies could then be developed to prevent these long-term abnormalities, instead of relying on asthma medication (especially inhaled corticosteroids) as is the current practice. Preventative strategies could include encouraging the development of specific vaccines.Read moreRead less