Dissecting Apoptosis And IL-15 Dependent Homeostasis Pathways Of Natural Killer (NK) Cells
Funder
National Health and Medical Research Council
Funding Amount
$423,809.00
Summary
We will investigate how the cytokine IL-15 regulates the homeostasis of natural killer (NK) cells. NK cells are critical for immune responses against invading viruses or bacteria or upon detection of transformed cells. NK cells are primed to attack infected or transformed cells and are rapidly activated by direct interaction or by soluble signals. Knowledge of how NK cells development and how their numbers and function are controlled is paramount to understanding infectious disease immunology an ....We will investigate how the cytokine IL-15 regulates the homeostasis of natural killer (NK) cells. NK cells are critical for immune responses against invading viruses or bacteria or upon detection of transformed cells. NK cells are primed to attack infected or transformed cells and are rapidly activated by direct interaction or by soluble signals. Knowledge of how NK cells development and how their numbers and function are controlled is paramount to understanding infectious disease immunology and developing better immuno-therapies.Read moreRead less
The Mechanisms Of Epithelial Cell Survival That Govern Thymus Function
Funder
National Health and Medical Research Council
Funding Amount
$620,967.00
Summary
The thymus is an organ dedicated to the production of crucial immune cells, called T lymphocytes. Cancer treatments, such as radiation or chemotherapy, destroy thymic function and impair immune recovery in patients. We aim to uncover molecular processes that govern the life and death decisions of cells in the thymus. Our goal is to then use this information to develop treatments to protect this critical organ from damage and improve immune recovery following radiation or chemotherapy.
Cytotoxic T Lymphocyte Synapse Formation And Serial Killing: When Breaking Up Is Hard To Do.
Funder
National Health and Medical Research Council
Funding Amount
$626,688.00
Summary
Killer T cells are a specialised group of immune cells, which destroy cancerous and infected cells. When killer T cells find a target, they attach and secrete toxic molecules. It then detaches from the dying target, so that it may go on to kill other cells. If it doesn’t detach properly, it remains bound to the target cell and results in an improper immune response. This proposal will investigate how the killer cell detaches, which is essential for an efficient immune response.
Antigen-presenting cells control immune responses. Different types of these cells do different jobs and affect different diseases. We wish to control these processes by determining how the cells live and die. In particular we are interested in controlling the local immune responses during rejection of islet transplantation, which can cure type 1 diabetes.
Controlling Life And Death Of Dendritic Cell Subsets For Immunomodulation
Funder
National Health and Medical Research Council
Funding Amount
$639,577.00
Summary
Dendritic cells are pivotal in orchestrating immune responses; for example, they can turn immune cells into assassins to kill virus infections. Their function is so diverse that different dendritic cells do different jobs. There are many genes that control life and death of cells but those that are important for each specialised dendritic cell have not been comprehensively studied. Drugs that affect the proteins made by such genes selectively may be a new way of controlling immune responses.
The Cell Death Mechanisms That Control Regulatory T Cell Homeostasis
Funder
National Health and Medical Research Council
Funding Amount
$583,782.00
Summary
A central question in immunology is how to prevent destructive immune responses (e.g. autoimmune disease) and initiate productive immune responses (e.g. against cancer). A major breakthrough in this area was the discovery of special immune cells, called a Regulatory T Cells. We propose to discover the genes that determine whether these cells live and die. We will use this information to control appropriate numbers and function of Regulatory T Cells to modify the immune system.
Quantifying the adaptive immune response. The aim of this project is to develop mathematical models and computer software capable of predicting immune responses in infection and disease. The ability to predict immune responses should allow better vaccine design and better understanding of what causes the immune system to attack its own body, causing autoimmune disease, or fail to respond, causing immunodeficiency. The models and software will also be applicable to other areas of cell biology, ....Quantifying the adaptive immune response. The aim of this project is to develop mathematical models and computer software capable of predicting immune responses in infection and disease. The ability to predict immune responses should allow better vaccine design and better understanding of what causes the immune system to attack its own body, causing autoimmune disease, or fail to respond, causing immunodeficiency. The models and software will also be applicable to other areas of cell biology, such as describing growth and development. Thus, this project will lead to advances in understanding of fundamental biology, as well as potential improvements in treatments for a range of diseases.Read moreRead less
Cellular Activation And Apoptosis In Response To Foreign Cytoplasmic DNA
Funder
National Health and Medical Research Council
Funding Amount
$496,446.00
Summary
Viruses are simple organisms. They grow within cells, needing host cell proteins for their replication. Viruses have only a few proteins of their own, and evolve rapidly to change these. It is therefore challenging for the immune system to identify viral infections. Recently it has been recognised that the genetic material of viruses (DNA or RNA) is detected by the immune system. A novel pathway for recognition of viral double stranded DNA is emerging. The genetic material of mammalian cells (DN ....Viruses are simple organisms. They grow within cells, needing host cell proteins for their replication. Viruses have only a few proteins of their own, and evolve rapidly to change these. It is therefore challenging for the immune system to identify viral infections. Recently it has been recognised that the genetic material of viruses (DNA or RNA) is detected by the immune system. A novel pathway for recognition of viral double stranded DNA is emerging. The genetic material of mammalian cells (DNA) is found within the membrane-bound nucleus of the cell. The presence of DNA outside the nucleus in the cytoplasm is abnormal, and is detected as an indication of viral infection. This causes either death of the cell, or activation to produce anti-viral molecules. We have identified a protein from the cytoplasm of cells which binds specifically to DNA. This protein, X is found in association with foreign DNA within 5 minutes of it being introduced into the cell. In this project we propose to confirm that X recognises foreign DNA and initiates cellular activation or death. Other molecules to which X binds during this process will be identified. This project is relevant to a number of problems in health and disease as well as biotechnology. In both gene therapy and biotechnology, DNA is introduced into cells in order to allow those cells to make specific proteins. The cell sees the introduced DNA as a potential viral infection, and it responds in ways which limit the production of the desired proteins. Lupus is an autoimmune disease with high levels of DNA in circulation. X is proposed as a protein involved lupus in mouse models. We suggest that DNA taken up by cells is recognised by X and this contributes to the disease. Understanding the means by which DNA is recognised in the cytoplasm may allow the development of much more efficient processes for gene therapy and protein production in biotechnology, and more effective lupus and antiviral therapies.Read moreRead less
The effect of age on regulatory T cell control of the innate and adaptive antiviral immune responses. Viral pathogens are a lead cause of infant mortality in the world. This project will define how T regulatory cells limit protective antiviral immune responses in the young. This information is critical for the development of potent antiviral vaccines that are effective from the newborn period without inducing autoimmunity. It will also provide novel insight into the way T regulatory cells can b ....The effect of age on regulatory T cell control of the innate and adaptive antiviral immune responses. Viral pathogens are a lead cause of infant mortality in the world. This project will define how T regulatory cells limit protective antiviral immune responses in the young. This information is critical for the development of potent antiviral vaccines that are effective from the newborn period without inducing autoimmunity. It will also provide novel insight into the way T regulatory cells can be manipulated both to dampen immunity, which can be used to develop strategies to reduce immune mediated disease and limit transplant rejection. Read moreRead less
Defining The Immunoregulatory Function Of Roqin: A Novel Gene Essential For Preventing Autoimmunity
Funder
National Health and Medical Research Council
Funding Amount
$721,250.00
Summary
Lupus is a systemic autoimmune disease that carries significant morbidity and mortality. Virtually any organ can be affected, including kidneys, brain and blood. Lupus is the result of a breakdown in normal regulation of the immune system. Although there is clearly a significant genetic contribution to lupus, few causative genes have been found in humans with this disease. Recently, we discovered a novel mutation in a new gene (named roqin), that cases lupus in mice. Based on preliminary investi ....Lupus is a systemic autoimmune disease that carries significant morbidity and mortality. Virtually any organ can be affected, including kidneys, brain and blood. Lupus is the result of a breakdown in normal regulation of the immune system. Although there is clearly a significant genetic contribution to lupus, few causative genes have been found in humans with this disease. Recently, we discovered a novel mutation in a new gene (named roqin), that cases lupus in mice. Based on preliminary investigations and prediction based on the structure of Roqin, we suspect that this gene may be a key immune regulator. Specifically, it is likely to be involved in maintenance of immunological self-tolerance, which normally prevents development of autoimmunity. Mice carrying the Roqin mutation have an abnormality of their T cells, which causes them to be abnormally activated, divide more readily and survive for longer. Hyperactivated T cells induce B cells to proliferate and secrete antibodies against self-tissues that eventually lead to loss of platelets, kidney damage, enlarged spleen and lymph nodes, and early death. We now want to investigate precisely how Roqin causes abnormal T cell activation. The protein sequence of Roqin predicts the existence of two zinc finger domains that are highly conserved across species and play critical functions in regulating cell growth. One of the zinc fingers is a RING domain known to have a ubiquitin-ligase activity, which is known to play a crucial role in negative regulation of lymphocyte signalling, and maintenance of tolerance. The other zinc finger domain is known to be important for destabilizing mRNA of cytokines, thereby influencing communication between lymphocytes. Elucidation of this novel mechanism of disease will help understand the cause of human lupus. It will also provide clues about more specific drug therapies that might be more efficacious, and carry less toxicity than those currently available.Read moreRead less