This Program Grant has three investigators, Professor Denis Moss, Dr Rajiv Khanna and Dr Scott Burrows, each of whom has collaborated on two previous Program Grants. The group is well known in the area of herpesvirus immunology and have published numerous scientific papers in leading medical journals. This program grant focuses on two human herpesviruses. The first is called Epstein-Barr virus which causes glandular fever and is associated with arange of human cancers. The second virus is human ....This Program Grant has three investigators, Professor Denis Moss, Dr Rajiv Khanna and Dr Scott Burrows, each of whom has collaborated on two previous Program Grants. The group is well known in the area of herpesvirus immunology and have published numerous scientific papers in leading medical journals. This program grant focuses on two human herpesviruses. The first is called Epstein-Barr virus which causes glandular fever and is associated with arange of human cancers. The second virus is human cytomegalovirus which can cause birth defects and problems in transplant patients. In this program we are investigating how the body�s immune system controls these viruses to exploit this information to develop new treatments.Read moreRead less
Antigen Dose And TCR Repertoire In CD8+ T Cell Immunodominance Hierarchies
Funder
National Health and Medical Research Council
Funding Amount
$558,920.00
Summary
The CD8+, or killer , T lymphocytes (white blood cells) are the hit men of immunity, recirculating continually around the body to eliminate other cells that are dangerous because they are cancerous or infected with a virus. A major difficulty is that killer T cells also exert selective pressures that cause viruses and tumours to mutate and thus avoid immune control. This is a particularly serious problem for RNA viruses that readily mutate as they divide. These include the human immunodeficiency ....The CD8+, or killer , T lymphocytes (white blood cells) are the hit men of immunity, recirculating continually around the body to eliminate other cells that are dangerous because they are cancerous or infected with a virus. A major difficulty is that killer T cells also exert selective pressures that cause viruses and tumours to mutate and thus avoid immune control. This is a particularly serious problem for RNA viruses that readily mutate as they divide. These include the human immunodeficiency virus (HIV) that causes AIDS and, while the mutations that are most important with influenza viruses are those that modify viral surface proteins recognized by antibodies, such T cell escape mutants can also be a problem with influenza. The other reason why there is particular interest in promoting CD8+ T cell-mediated immunity to influenza is that the killer T cells are very cross-reactive. We have shown that vaccination approaches that prime mouse CD8+ T cells to resist influenza A viruses circulating currently in humans will also protect against the highly lethal, and dangerous H5N1 bird 'flu. The present flu vaccines only stimulate antibodies, so there is interest in the possibility of a major re-design. The CD8+ T cells recognize tiny elements (peptides) of the virus or tumour bound in the tip of our own transplantation, or class I major histocompatibility complex (MHCI) molecules. These pMHCI complexes are called epitopes. The focus here is on the use of novel genetic engineering strategies to find out how, when the virus mutates to disrupt the major epitopes seen by killer T cells, other minor epitopes can be abnormally emphasized in a way that promotes effective immune control. As we work on this with the relatively simple and safe influenza model we will concurrently develop strategies that may be of value in HIV and tumour immunity. Solving this problem could prove to be a substantial advance in the design of vaccines and immunotherapy approaches.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
The Importance Of GM-CSF In Determining The Fate And Function Of Dendritic Cell (DC) Subsets: Resident DC, Inflammatory DC And Suppressive DC.
Funder
National Health and Medical Research Council
Funding Amount
$334,053.00
Summary
The hormone GM-CSF determines how infections are seen by the immune system GM-CSF is a hormone already in use for increasing the production of white blood cells. We have found that it also affects their function, especially that of specialised white blood cells that process infectious materials to be recognised by the immune system. This project aims to detail the effects of GM-CSF on specialised white blood cells.
Investigating CD4+ T Helper Cell Differentiation During Blood-stage Plasmodium Infection
Funder
National Health and Medical Research Council
Funding Amount
$408,388.00
Summary
Some infections tend to afflict us only once, e.g. chickenpox, because our bodies develop immunity to these microbes relatively easily. In contrast, it takes many infections to develop immunity to the malaria parasite, because our immune systems seem to respond inefficiently to it. My work will improve our understanding of how the immune system is poorly activated during malaria, and may provide new ideas for boosting the immune system in response to malaria or indeed other infections.
Cytokine Production By Human Dendritic Cells - Is Less More?
Funder
National Health and Medical Research Council
Funding Amount
$378,107.00
Summary
Dendritic cells (DC) are specialist white blood cells responsible for initiating and coordinating immune responses against pathogens and cancer. DC act as sentinels of the immune system and are found throughout the body where they are in constant surveillance for infections or danger signals. Once armed they traffic to the lymph nodes, where they activate T lymphocytes and NK cells, which are then responsible for mounting an attack against the infection or tumour. The complex mechanisms of how d ....Dendritic cells (DC) are specialist white blood cells responsible for initiating and coordinating immune responses against pathogens and cancer. DC act as sentinels of the immune system and are found throughout the body where they are in constant surveillance for infections or danger signals. Once armed they traffic to the lymph nodes, where they activate T lymphocytes and NK cells, which are then responsible for mounting an attack against the infection or tumour. The complex mechanisms of how dendritic cells respond to danger, and how they direct T and NK cells to induce specific immune responses appropriate for a particular infection are poorly understood. Most of our current knowledge of DC has been obtained from mouse studies, and it is believed that secretion of cytokines by dendritic cells play an important role. Human dendritic cells have been difficult to identify, however we have pioneered methods to isolate and characterise them from human tissue. We will therefore investigate the production of cytokines from human DC subsets and the role they play in the induction of immune responses. DC can be instructed in the test tube to recognise a cancer and mount an immune response, and this is a promising new therapy for cancer. Our work will uncover fundamental information about the most potent danger signal, the type of DC and the most important cytokines for inducing immune responses against cancers, and will therefore assist in the development of cancer vaccines.Read moreRead less
HIV is one of the highest public health priorities of our time. Traditional vaccines have been unsuccessful highlighting the need for alternative approaches to HIV vaccine design. We propose to modify a novel technology developed initially for targeted drug delivery, termed “capsules”, for the purpose of inducing an immune response. This is a generic technology with applications for other infectious diseases and cancer and brings together disparate disciplines of nanochemistry and immunology.
Molecular Regulation Of Tim3 Signalling In T Cells
Funder
National Health and Medical Research Council
Funding Amount
$366,252.00
Summary
Chronic inflammatory diseases like multiple sclerosis and cancer can be rectified via interventions of T cell checkpoint pathway. Tim3 is a T cell checkpoint molecule that is gaining extreme interest in these diseases. Here, we aim to identify molecular mechanism(s) to suppress or enhance Tim3 signalling in effector T cell, potentially leading to the development of therapeutic intervention to treat autoimmune disorders and cancers.