WHAT IS THE RELATIVE ROLE OF TNF-RELATED APOPTOSIS-INDUCING LIGAND (TRAIL) IN TUMOR IMMUNITY?
Funder
National Health and Medical Research Council
Funding Amount
$85,660.00
Summary
Programmed cell death is a physiological process integral to the development and functioning of the immune system. A better understanding of the cellular effector cells and molecules that mediate cell death will provide valuable insight into designing better immunotherapeutic treatments of cancer. Members of the tumor necrosis factor (TNF) family of hormones and receptors are critically involved in the process of cell death. Within this family, several members have been well characterised and th ....Programmed cell death is a physiological process integral to the development and functioning of the immune system. A better understanding of the cellular effector cells and molecules that mediate cell death will provide valuable insight into designing better immunotherapeutic treatments of cancer. Members of the tumor necrosis factor (TNF) family of hormones and receptors are critically involved in the process of cell death. Within this family, several members have been well characterised and their functions ascribed. Some play an important role in the maintenance of immune cells , others in the movement of immune cells and organisation of lymphoid tissues. This proposal seeks to define the function of the recently discovered TNF-related apoptosis-inducing ligand (TRAIL). TRAIL mediates cell death of cancerous cells in culture but does not kill most normal tissues. This specificity for diseased tissue makes TRAIL a very promising candidate as an anti-tumor therapeutic. Until recently, very little was known regarding the natural physiological role of TRAIL. We have recently described the expression of TRAIL on liver natural killer cells and the anti-tumor activity of TRAIL against primary tumors and metastases. Importantly, TRAIL function appears to be regulated by an inflammatory mediator called interferon. We now wish to explore the role of TRAIL in tumor immunotherapies and tumor surveillance that requires interferon.Read moreRead less
Making Signalling Through The Tumour Necrosis Factor Receptors Selective For Promoting Neutrophil Antimicrobial Activity
Funder
National Health and Medical Research Council
Funding Amount
$196,312.00
Summary
It is evident to the professional and general community that antibiotic and drug resistance displayed by bacteria is a continuing and growing problem in the treatment of infection with potentially casastrophic effect on the health of our community. This concern is only partly reduced by our potential to develop new antimicrobial agents and vaccines. If we were able to use immunomodulators in a relatively safe and appropriate manner to target and enhance the antimicrobial power of specific compon ....It is evident to the professional and general community that antibiotic and drug resistance displayed by bacteria is a continuing and growing problem in the treatment of infection with potentially casastrophic effect on the health of our community. This concern is only partly reduced by our potential to develop new antimicrobial agents and vaccines. If we were able to use immunomodulators in a relatively safe and appropriate manner to target and enhance the antimicrobial power of specific components of the immune system then this could be exploited in the treatment of infection. While body proteins formed (cytokines) which modify the behaviour of the immune system are being used as pharmaceuticals, their toxic side effects are problematic to the patient. Our project focusses on one of the cytokines, tumor necrosis factor (TNF), which increases the antimicrobial activity of phagocytic cells but in addition can have quite devastating effects on other tissues in the body. This is because when TNF binds to its receptor on cells and tissues it elicits a multitude of signals inside the cell which can also precipitate illness. The purpose of our investigations is to identify which signals are responsible for increasing resistance against infection and which are not. With this information we will then see if it is feasible to selectively stimulate this signal from outside the cell since this has a better chance of succeeding as a pharmaceutical. This task is likely to be achievable since our research team has made some unique observations about TNF signalling characteristics and we have developed a peptide TNF mimetic which shows only the characteristics of increasing antimicrobial activity.Read moreRead less
Defining The Roles Of TNF, Lymphotoxin Alpha And LIGHT In Experimental Visceral Leishmaniasis
Funder
National Health and Medical Research Council
Funding Amount
$410,148.00
Summary
Visceral leishmaniasis (VL) is an important human disease caused by the protozoan parasites Leishmania donovani and L. infantum (chagasi). Studies in experimental VL caused by L. donovani infection of mice have resulted in major insights into the causes of VL and the reasons why VL patients become severely immunocompromised. Work from our laboratory has shown that members of the TNF family of cytokines play key roles in the generation of effective immune responses during VL, but also mediate sig ....Visceral leishmaniasis (VL) is an important human disease caused by the protozoan parasites Leishmania donovani and L. infantum (chagasi). Studies in experimental VL caused by L. donovani infection of mice have resulted in major insights into the causes of VL and the reasons why VL patients become severely immunocompromised. Work from our laboratory has shown that members of the TNF family of cytokines play key roles in the generation of effective immune responses during VL, but also mediate significant tissue pathology, particularly in the spleen, following L. donovani infection. In this grant, we will define the roles of several key members of the TNF family in the generation of immunity and pathology during experimental VL. We will also test if the activity of these molecules can be modulated to control disease without detrimental side effects. Results from this research have implication for the design of new vaccines and therapeutics to control VL. In addition, given the important role of TNF family members in cancers and autoimmune diseases, the work in this grant will have advance our understanding of pathogenic processes that are common to many important human diseases.Read moreRead less
Regulation Of Tissue-type Plasminogen Activator Gene Expression In Endothelial Cells And In Transgenic Mice
Funder
National Health and Medical Research Council
Funding Amount
$244,009.00
Summary
Tissue-type plasminogen activator (t-PA) is an enzyme which plays an important role in the removal of blood clots from the circulation. One of the major sites of production of t-PA are endothelial cells which line the blood vessel wall. The rate of t-PA production is greatly influenced by factors released from other cells. One of these factors is tumour necrosis factor (TNF). The t-PA gene is switched off in endothelial cells exposed to TNF. One of the aims of this project is to understand how t ....Tissue-type plasminogen activator (t-PA) is an enzyme which plays an important role in the removal of blood clots from the circulation. One of the major sites of production of t-PA are endothelial cells which line the blood vessel wall. The rate of t-PA production is greatly influenced by factors released from other cells. One of these factors is tumour necrosis factor (TNF). The t-PA gene is switched off in endothelial cells exposed to TNF. One of the aims of this project is to understand how the t-PA gene is suppressed by TNF in human endothelial cells and in transgenic mice. The transgenic mice we have available express the regulatory region of the t-PA gene (called the gene promoter) connected to a reporter gene called LacZ. We will use these animals to visualise the expression pattern of LacZ expression under normal conditions and in mice treated with TNF. The results of these experiments will provide new information as to how the t-PA gene is controlled in cells and in the body.Read moreRead less
The Role Of TNF Family Members TWEAK And TNF-alpha In Bone Remodelling
Funder
National Health and Medical Research Council
Funding Amount
$566,946.00
Summary
Bone remodelling, or turnover, is the process by which bone is broken down by osteoclasts and replaced by osteoblasts. Disruption of this process is the cause of many bone-related diseases that affect millions of Australians and countless others worldwide. It is controlled by the complex interactions of a large number of systemic factors (hormones) and locally acting agents, such as chemokines and cytokines, the details of which are not fully understood. Each of these factors, however, is a pote ....Bone remodelling, or turnover, is the process by which bone is broken down by osteoclasts and replaced by osteoblasts. Disruption of this process is the cause of many bone-related diseases that affect millions of Australians and countless others worldwide. It is controlled by the complex interactions of a large number of systemic factors (hormones) and locally acting agents, such as chemokines and cytokines, the details of which are not fully understood. Each of these factors, however, is a potential therapeutic target. Pro-inflammatory cytokines, those that are associated with inflammatory diseases such as Rheumatoid Arthritis (RA), are known to have key roles in both the physiology and pathology of bone. TWEAK is a recently described member of the TNF family of cytokines. We have shown that TWEAK is a novel mediator of inflammatory arthritis in mouse model systems and is therefore a likely candidate as a therapeutic target. We now have extensive preliminary data to suggest that TWEAK is involved in human RA, and also in the regulation of normal bone remodelling. TWEAK therefore may be implicated in a wide spread of bone diseases, including osteoporosis. We believe it is of great importance to perform a thorough analysis of TWEAK in bone biology, and we propose to do so.Read moreRead less
A Novel Viral Modifier Of TNF Family Receptor Signalling: Elucidation Of Mechanisms Of Action
Funder
National Health and Medical Research Council
Funding Amount
$453,727.00
Summary
Over millions of years, viruses have evolved a great number of strategies to allow them to subvert the effectiveness of the host response. We have discovered that one of these viral strategies seems designed to block the synthesis of an important anti-viral factor, called tumour necrosis factor. In this project, we aim to work out how the viral factor blocks tumour necrosis factor production inside the cell, at the level of the molecules involved. The second aspect of this project concerns the i ....Over millions of years, viruses have evolved a great number of strategies to allow them to subvert the effectiveness of the host response. We have discovered that one of these viral strategies seems designed to block the synthesis of an important anti-viral factor, called tumour necrosis factor. In this project, we aim to work out how the viral factor blocks tumour necrosis factor production inside the cell, at the level of the molecules involved. The second aspect of this project concerns the identification of the types of cells and responses which the viral factor acts upon to manipulate the host response. We reason that this information will improve our understanding of how tumour necrosis factor production is regulated and the significance of this type of response in virus infection and physiology, more generally. The application of this research will be to aid the design of better drugs for the treatment of many conditions where tumour necrosis factor production contributes significantly to pathology, eg rheumatoid arthritis and autoimmunity. In some conditions, it may be a therapeutic advantage to selectively turn on tumour necrosis factor, eg for treatment of infections or cancer.Read moreRead less
Regulation Of TNF And SFK Signalling In Immune Cells By TCPTP
Funder
National Health and Medical Research Council
Funding Amount
$454,023.00
Summary
Tumour necrosis factor (TNF) is a potent proinflammatory cytokine that plays an important role in immunity and inflammation. TNF acts on the cell surface to activate two key cellular communication or signalling pathways: the mitogen-activated protein kinase (MAPK) pathway and the nuclear factor kappaB (NFkappaB) pathway. The relative activation of the two pathways can dictate whether cells live and proliferate or differentiate or otherwise die in response to TNF, and therefore determine the natu ....Tumour necrosis factor (TNF) is a potent proinflammatory cytokine that plays an important role in immunity and inflammation. TNF acts on the cell surface to activate two key cellular communication or signalling pathways: the mitogen-activated protein kinase (MAPK) pathway and the nuclear factor kappaB (NFkappaB) pathway. The relative activation of the two pathways can dictate whether cells live and proliferate or differentiate or otherwise die in response to TNF, and therefore determine the nature of the immune or inflammatory response. The T-cell protein tyrosine phosphatase (TCPTP) is known to be important in the immune system and serves as a negative regulator of inflammation. Our preliminary studies have identified TCPTP as a selective regulator of TNF-induced MAPK but not NFkappaB signaling. TCPTP exerts its effects by inactivating Src family kinases (SFK) which are themselves integral to immune and inflammatory responses. In this proposal we will elucidate the molecular basis for TCPTP function in TNF- signalling and characterise the role of TCPTP in TNF and SFK functions in immune cells, in particular T-cells.Read moreRead less