Epigenetic Regulation Of CD8+ T Cell Function And Memory.
Funder
National Health and Medical Research Council
Funding Amount
$578,171.00
Summary
Upon virus infection, a subset of white blood cells, called killer T cells, are recruited to fight the infection. This proposal aims to examine molecular changes that occur within killer T cells and impart their specific function. We also aim to understand how killer T cells are _programmed� as they establish immunological memory. This proposal will provide insights important for the design and improvement of vaccine strategies to fight pathogens such as influenza, HIV and even tumors.
Memory CD4 T Cells That Harbour The Reservoir Of Latent HIV Infection: Their Antigen Specificity, Function And Frequency Of Antigen-driven Reactivation
Funder
National Health and Medical Research Council
Funding Amount
$453,782.00
Summary
Current antiretroviral therapy for HIV successfully suppresses virus production, but does not completely eliminate the virus from the body. This project will provide essential information on memory CD4 T cells that retain HIV in a latent DNA form. Memory CD4 T cells can be very long-lived, and these latently infected memory cells can give rise to virus during treatment interruption. We will use a novel method to identify which memory CD4 T cells contain latent HIV DNA.
Investigations Into The Biology And Functionality Of The Human T Cell Receptor
Funder
National Health and Medical Research Council
Funding Amount
$424,262.00
Summary
T lymphocytes play a pivotal role in the immune system by recognising virus-infected tissue and tumour cells through the use of specific cell surface receptors called T cell receptors (TCR). This project will study why partcular TCRs are used by the immune system, and will also examine the specificity of T cell recognition by determine the range of molecules an individual T cell can recognise. The work will aid in the development of new intelligent vaccines for cancer and infectious disease.
Direct Characterisation Of Naive Epitope-specific T Cell Populations And Their Influence On Immune Responses
Funder
National Health and Medical Research Council
Funding Amount
$314,983.00
Summary
CytotoxicT cells (CTLs) recognize and remove virus infected cells. Both the number and the diversity of T cells involved in the response influence viral clearance. We plan to use a novel technology to directly analyze the numbers and diversity of such CTLs in mice prior to infection. This will clarify how characteristics of cell populations prior to infection define the immune response after infection. This is critical for vaccine design to maximize the efficiency of the immune response.
The Generation Of HSV-1 Specific Effector And Memory CD4+ T Cell Responses.
Funder
National Health and Medical Research Council
Funding Amount
$460,509.00
Summary
This proposal aims to determine the mechanisms underpinning the generation of helper T cell responses following HSV-1 infection. It will determine the factors that allow T cells to access sites of viral replication and the mechanisms by which they provide protection from skin infections.
Influence Of TCR Signals From Contact With Self-MHC Ligands On Naive T Cell Survival
Funder
National Health and Medical Research Council
Funding Amount
$418,658.00
Summary
A diverse repertoire of naive T cells constitutes a critical part of the adaptive immune system and protects hosts from various infections and cancer. T cells are stably maintained at a constant number in the periphery by mechanisms that are not clearly understood. This proposal will shed light on how the immune system preserves a diverse na�ve T cell pool able to respond against various foreign antigens, while preventing their harmful auto-reactivity to self antigens.
Autoimmune diseases constitute a significant medical problem in the developed world and are increasing in incidence. Many control mechanisms exist in the body, but in people with genetic susceptibility to autoimmune disease, the mechanisms fail and the body's immune system attacks normal tissues or organs. We have developed a new approach, using the cells which train the immune system, to re-educate the cells that would otherwise attack normal healthy tissues in autoimmune-prone individuals. The ....Autoimmune diseases constitute a significant medical problem in the developed world and are increasing in incidence. Many control mechanisms exist in the body, but in people with genetic susceptibility to autoimmune disease, the mechanisms fail and the body's immune system attacks normal tissues or organs. We have developed a new approach, using the cells which train the immune system, to re-educate the cells that would otherwise attack normal healthy tissues in autoimmune-prone individuals. These cells (dendritic cells) are genetically modified to express the molecular targets of the autoimmune response. This in turn switches off the response to these targets. In this project, we will explore how these cells can be used to turn off the harmful cells present in the immune system.Read moreRead less
Effector And Memory CD8+ T Cell Responses To Engineered Influenza A Escape Mutants
Funder
National Health and Medical Research Council
Funding Amount
$465,210.00
Summary
T cells are a critical component of the immune system after infection with viruses. In particular, virus-specific CD8+ T cells can clear viral infections by killing virally-infected cells and the release of immunomodulators. These are called effector T cells. After the viral infection is cleared, a small proportion of T cells (around 5 to 10%) survives for many years and constitute a memory pool of virus-specific T cells. Memory T cells provide a rapid and effective protection in case of a repea ....T cells are a critical component of the immune system after infection with viruses. In particular, virus-specific CD8+ T cells can clear viral infections by killing virally-infected cells and the release of immunomodulators. These are called effector T cells. After the viral infection is cleared, a small proportion of T cells (around 5 to 10%) survives for many years and constitute a memory pool of virus-specific T cells. Memory T cells provide a rapid and effective protection in case of a repeated infection with the same virus, and hence result in a less severe disease. However, viruses often mutate their genes to escape such efficient T cell responses. In this study, we will investigate T cell responses after infection with mutated strains of influenza viruses. We will engineer a panel of mutant influenza viruses, which alter the nature and characteristics of T cells. We will analyse how efficient are these T cells and whether they can protect against a normal strain of influenza A. Subsequently, we will characterise quantitative and qualitative aspects of memory T cell pools after infection with mutant influenza viruses. Since a number of viruses such as influenza, HIV and HCV rapidly mutate their genes, our study will not only address the question of T cell responses to mutated influenza viruses, but also will provide an excellent model for investigating protective T cell responses to other viral infections.Read moreRead less
Mechanisms Of Rapid Memory CD8+ T-cell Inactivation
Funder
National Health and Medical Research Council
Funding Amount
$318,517.00
Summary
Type 1 diabetes (T1D) and other autoimmune diseases results from misdirected immune responses that destroy normal body tissues. The ultimate goal of therapeutic strategies is to remove or inactivate the immune cells that attack normal tissues, while leaving other immune cells, for example, those required for protection from infectious diseases and tumours, unaffected. Here we propose to test a new way of turning off inappropriate immune reactions.
The Role Of C-Cbl In The Regulation Of T Cell Signalling And Development
Funder
National Health and Medical Research Council
Funding Amount
$527,250.00
Summary
c-Cbl is a member of a multi-adaptor protein family that can interact with many signalling proteins via its different domains. Cbl proteins have been implicated as negative regulators of signalling pathways involving protein tyrosine kinases (PTKs). PTKs are enzymes which add phosphate groups to tyrosine residues on other protein substrates, and the process of tyrosine phosphorylation acts as a potent biochemical switch to turn signalling cascades on and off. Studies of Cbl-deficient (knockout) ....c-Cbl is a member of a multi-adaptor protein family that can interact with many signalling proteins via its different domains. Cbl proteins have been implicated as negative regulators of signalling pathways involving protein tyrosine kinases (PTKs). PTKs are enzymes which add phosphate groups to tyrosine residues on other protein substrates, and the process of tyrosine phosphorylation acts as a potent biochemical switch to turn signalling cascades on and off. Studies of Cbl-deficient (knockout) mice show that Cbl proteins are important in regulating the development of, and signalling by, cells of the immune system called T cells. c-Cbl knockout mice show greatly enhanced PTK-signalling responses and deregulated activity of a PTK called ZAP-70. The mechanism of this is not known, but analysis of a c-Cbl mutant mouse shows that this is not dependent on the tyrosine kinase binding (TKB) domain of c-Cbl. Therefore other functional domains of Cbl must be responsible for the increased signalling response in the c-Cbl knockout mouse. One candidate is the highly conserved RING finger domain which can modify Cbl-associated PTKs by addition of ubiquitin molecules. Ubiquitination of a protein often, but not always, leads to its degradation, and this could be how Cbl controls the strength and duration of signalling in T cells. However there may be other functions of the conserved RING finger yet to be identified. c-Cbl itself is prominently and very rapidly modified by tyrosine phosphorylation on tyrosine 737 by the Fyn PTK following T cell activation, but the role of this modification is not known and could also be essential for c-Cbl s function in T cells. We plan to investigate the roles of the RING finger domain and Fyn-mediated tyrosine phosphorylation in c-Cbl regulation of T cell signalling by analyzing knock-in mice that carry specific mutations disrupting the RING finger or tyrosine 737 in the c-Cbl gene.Read moreRead less