Developmental Stages Of In Vivo And In Vitro-generated Dendritic Cell Subsets And Regulation Of T Cell Differentiation.
Funder
National Health and Medical Research Council
Funding Amount
$88,087.00
Summary
Dendritic cells (DC) represent a diverse family of white blood cells that form a sentinel network throughout the body involved in the detection and eradication of pathogens and cancer cells. DC can originate from different precursor cells in the bone marrow. It is therefore possible that different types of DC perform differing functions. For instance, DC not only initiate immune responses but are also able to silence them. However, the ability of DC to instruct and orchestrate the immune respons ....Dendritic cells (DC) represent a diverse family of white blood cells that form a sentinel network throughout the body involved in the detection and eradication of pathogens and cancer cells. DC can originate from different precursor cells in the bone marrow. It is therefore possible that different types of DC perform differing functions. For instance, DC not only initiate immune responses but are also able to silence them. However, the ability of DC to instruct and orchestrate the immune response may not only depend upon their origins but also on where they encounter pathogens or cancer cells and what other signals are associated with this encounter. Due to their specialized capacity to instruct the immune response (e.g. T cells, B cells and NK cells) of impending danger, DC are used experimentally to more efficiently deliver vaccines to the immune response so as to eradicate cancer or infectious disease. However, in order to successfully use DC to deliver vaccines, one must first understand how these cells normally behave in the body and what signals can alter their functional ability to orchestrate immune responses. We can generate DC outside the body from their precursors. We can also isolate DC from the circulation. This project seeks to identify how various physiologic stimuli differentially regulate the functional behaviour of DC subsets and how this then influences the DC's ability to instruct the developing T cell immune response. Furthermore, whether these signals are the same for DC generated outside the body with those isolated from the blood. Of particular interest is whether differing types of DC and differing stages of their maturity will differentially influence the T cell's ability to secrete immune response hormones and to recognize and kill cancer cells. The findings of this study have direct implications of how to best harness DC to effectively deliver vaccines and generate potent immune responses against cancer and infectious disease.Read moreRead less
Regulation Of Macrophage Function And Gene Expression By The Th2-Promoting Stimulus, ES-62
Funder
National Health and Medical Research Council
Funding Amount
$465,750.00
Summary
White blood cells are responsible for co-ordinating the immune response against foreign micro-organisms. Macrophages are a particular type of white blood cell that attempt to destroy microbes during the initial stages of an infection, but also release toxic substances that are responsible for pathology and side effects during many immune responses. This project aims to address how macrophages are involved in a particular type of immune response that develops when individuals are susceptible to c ....White blood cells are responsible for co-ordinating the immune response against foreign micro-organisms. Macrophages are a particular type of white blood cell that attempt to destroy microbes during the initial stages of an infection, but also release toxic substances that are responsible for pathology and side effects during many immune responses. This project aims to address how macrophages are involved in a particular type of immune response that develops when individuals are susceptible to certain diseases including asthma and diseases associated with intracellular infections. We are identifying genes expressed in macrophages during these immune responses that are likely to be involved in susceptibility to such diseases.Read moreRead less
The Molecular Identification Of FoxP3 +ve Regulatory T Cells
Funder
National Health and Medical Research Council
Funding Amount
$483,273.00
Summary
The immune system has a series of checks and balances in place to distinguish foreign bodies from normal, or self-antigens. In healthy individuals this prevents the immune system from attacking the cells and tissues of the body, food proteins, and the beneficial bacteria of the gut. However in autoimmune disease the system becomes imbalanced, allowing reactions to benign antigens, causing diseases such as diabetes, asthma and rheumatoid arthritis. One of the key players in the maintenance of a h ....The immune system has a series of checks and balances in place to distinguish foreign bodies from normal, or self-antigens. In healthy individuals this prevents the immune system from attacking the cells and tissues of the body, food proteins, and the beneficial bacteria of the gut. However in autoimmune disease the system becomes imbalanced, allowing reactions to benign antigens, causing diseases such as diabetes, asthma and rheumatoid arthritis. One of the key players in the maintenance of a healthy immune system is a specialized set of T cells known as T Regulatory cells. These cells are rare, at 1-4% of all T cells, yet are potent modulators of other T cells, and can prevent the activation of a T cell if it is reacting to a self-antigen. If they can control the cause of autoimmune disease, and patient Treg cells can be manipulated, it may be possible to use them therapeutically. Recently the switch that is required to generate regulatory cells was identified from patients with a rare autoimmune disease called Immunodysregulation, polyendocrynopathy, enteropathy, X-linked syndrome or IPEX. A mouse disease, Scurfy, with similar symptoms, is caused by the same mutations. The mutated gene encodes a protein, FoxP3, and this protein is able to bind to other genes in T cells and regulate their function. Without this protein, there are no T regulatory cells, resulting in autoimmune disorders. At this time there is very little known about how the FoxP3 gene is able to make a T cell become a regulatory T cell, and nothing is known about the genes that are turned off and on to facilitate this. If we can understand better the role of this protein, FoxP3, in the generation and maintenance of T cells with regulatory function, we may better be able to diagnose and treat autoimmune diseases, and this knowledge will have broad application to many autoimmune disorders.Read moreRead less
Development And Function Of NKT Cell Subsets In Humans
Funder
National Health and Medical Research Council
Funding Amount
$533,828.00
Summary
NKT cells are a type of white blood cell that help to control the function of the immune system. Many studies have reported an association between low NKT cell levels and increased rates of cancer and autoimmune diseases such as type 1 diabetes (T1D). Unfortunately, NKT cells are a relatively recent discovery and their function is not well understood, especially in humans. For example, it has only recently been discovered that there are different types of NKT cells with different functions. This ....NKT cells are a type of white blood cell that help to control the function of the immune system. Many studies have reported an association between low NKT cell levels and increased rates of cancer and autoimmune diseases such as type 1 diabetes (T1D). Unfortunately, NKT cells are a relatively recent discovery and their function is not well understood, especially in humans. For example, it has only recently been discovered that there are different types of NKT cells with different functions. This lack of knowledge has prevented us from understanding how NKT cells normally prevent disease, and how we should treat diseases associated with low NKT cell numbers. In this project, we will study human NKT cells to determine how many different subsets exist, how they develop, and what role they play in the immune system. Importantly, we will use our knowledge to compare NKT cells from healthy donors and patient groups with T1D and cancer to determine exactly what is wrong with the NKT cells in these people. While both diseases are already linked to low NKT cell numbers, we do not know how these problems arise, or if some types of NKT cells are more important than others. Our study will determine how different types of NKT cells develop and function in humans and therefore allow a much more detailed understandng of how to diagnose and treat NKT cell deficiencies associated with different diseases.Read moreRead less