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
Molecular Pathogenesis Of Herpes Simplex Virus Latency And Reactivation : Relationship With Viral Genomic Structure
Funder
National Health and Medical Research Council
Funding Amount
$217,060.00
Summary
A major target for antiviral drugs that combat herpes simplex infections, such as genital herpes and herpes encephalitis, is replication of viral DNA. There are significant gaps in the understanding of herpes simplex virus DNA replication which are addressed in this project. Further, a major factor responsible for the high impact of herpes simplex on the community is virus' ability to lie dormant (latent) in the body. The significance of lateny is that it periodically reactivates giving rise to ....A major target for antiviral drugs that combat herpes simplex infections, such as genital herpes and herpes encephalitis, is replication of viral DNA. There are significant gaps in the understanding of herpes simplex virus DNA replication which are addressed in this project. Further, a major factor responsible for the high impact of herpes simplex on the community is virus' ability to lie dormant (latent) in the body. The significance of lateny is that it periodically reactivates giving rise to recurrent infections. In molecular terms, latency is a reversible interruption of viral DNA replication, but the precise mechanisms involved are incompletely understood. This project explores ways in which latency might be established and reactivated. This information may eventually lead to improved strategies for reducing the burdens caused by herpes simplex virus infections.Read moreRead less
Mechanisms Of Immune Modulation By Human Cytomegalovirus During The Latent Phase Of Infection
Funder
National Health and Medical Research Council
Funding Amount
$165,500.00
Summary
Human cytomegalovirus (CMV) is a herpesvirus which infects a majority of the population. CMV is a significant cause of serious, life-threatening disease in neonates and in people who are immunosuppressed. Bone marrow and solid organ transplant recipients are particularly at risk of developing serious CMV disease. CMV has the remarkable ability to hide in the body in a dormant or latent form for the life of the host. However, when conditions are right the virus can awaken (ie reactivate) from its ....Human cytomegalovirus (CMV) is a herpesvirus which infects a majority of the population. CMV is a significant cause of serious, life-threatening disease in neonates and in people who are immunosuppressed. Bone marrow and solid organ transplant recipients are particularly at risk of developing serious CMV disease. CMV has the remarkable ability to hide in the body in a dormant or latent form for the life of the host. 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 reactivation from latency is of most medical significance, yet the latent phase of infection remains very poorly understood. We recently reported that during latent infection CMV interfered with the expression of a protein which plays a crucial role in our immune system. This protein is called MHC class II and its proper function is essential for our immune system to fight infections. Thus, we postulated that the ability of CMV to successfully hide in a cell in a latent state is at least partially due to its ability to interfere with the cells ability to properly make MHC class II proteins. This project aims to futher define and characterise the functions of latent CMV that enable it to interfere with our immune system. Firstly, we aim to continue with our studies to determine the mechanism by which latent CMV interferes with MHC class II expression. Secondly, we will seek to determine whether latent CMV interferes with any other important components of our immune system. Thirdly, we will seek to identify the precise viral gene that causes the interference with MHC class II expression. Determining the mechanism of immune system regulation and the viral gene(s) responsible for this interference may lead to the design of gene therapies to lessen the clinical impact of CMV disease in transplant recipients.Read moreRead less
Human Cytomegalovirus Gene Expression And Functions During Latent Infection And Reactivation
Funder
National Health and Medical Research Council
Funding Amount
$789,473.00
Summary
Human cytomegalovirus has the ability to hide in the body in a latent form for the life of the host. However, the virus can awaken (reactivate) from its latent state, producing new infectious virus and disease. It is in immunosuppressed people such as transplant patients that reactivation from latency causes significant morbitity and mortality, yet the latent infection remains very poorly understood. This project will identify and define the functions of viral genes that facilitate latency.
Molecular Investigations Of Antithrombin Instability And Heparin Binding Mechanism
Funder
National Health and Medical Research Council
Funding Amount
$195,691.00
Summary
Thrombosis is a significant disease affecting a large number of people. The primary treatment for episodes of acute thrombosis is administration of the anticoagulant, heparin. The effector molecule through which heparin carries out its action is the serine proteinase inhibitor, antithrombin. This molecule regulates blood clotting by inhibiting the proteinases which carry out this process. Antithrombin is converted from a poor inhibitor of coagulation proteases to a very good inhibitor on binding ....Thrombosis is a significant disease affecting a large number of people. The primary treatment for episodes of acute thrombosis is administration of the anticoagulant, heparin. The effector molecule through which heparin carries out its action is the serine proteinase inhibitor, antithrombin. This molecule regulates blood clotting by inhibiting the proteinases which carry out this process. Antithrombin is converted from a poor inhibitor of coagulation proteases to a very good inhibitor on binding heparin. This provides a control point for coagulation. The mechanism by which antithrombin is converted to a very good inhibitor of coagulation proteases involves a large change in the structure of this protein. These changes in structure are linked to the changes which occur when antithrombin becomes inactive through the process of polymerisation. Certain patients with thrombosis have been found to have changes in both the stability and heparin affinity of their antithrombin molecules, which forms the underlying basis for the disease. We wish to study the reasons for the effects of mutations in the antithrombin variants by making recombinant mutants which mimic the molecules in the thrombotic patients and carrying out detailed, sophisticated molecular analyses of their interaction with heparin and proteases and their stability under various conditions. Additionally we will engineer recombinant mutants of antithrombin which we believe will stabilise the molecule and potentially act as an improved supplement for therapy. This analysis will provide important insights into the functioning of both heparin and antithrombin and thereby significantly improve our understanding of the control of coagulation.Read moreRead less
Viral And Host Cell Gene Expression During The Establishment And Maintenance Phases Of Human Cytomegalovirus Latency
Funder
National Health and Medical Research Council
Funding Amount
$149,250.00
Summary
Human cytomegalovirus (CMV) 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 CMV disease. Like other herpesviruses, after initial infection CMV can establish a life-long latent infection. During latency, the virus remains dormant in the human body and ....Human cytomegalovirus (CMV) 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 CMV disease. Like other herpesviruses, after initial infection CMV 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. The overall aim of these studies is to provide a much better understanding of how CMV latency is established and maintained, with the ultimate goal of making advances for the design of anti-viral therapies to disrupt these processes. This project has three major components: Firstly, we aim to identify and characterise viral gene expression during the establishment of latency and these findings will 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 the establishment and maintenance phases of latency. Thirdly, we will apply microarray technologies to determine how human cell genes are altered in response to the expression of individual viral genes that are active during the latent phase of infection.Read moreRead less