Regulating Tolerogenic Signals By Inhibitory Co-receptors
Funder
National Health and Medical Research Council
Funding Amount
$265,500.00
Summary
Immunoreceptors play an important role in balancing the threshold of cellular activation is critical in the immune response to tumours, pathogens or allergens, to arrest autoimmune and infectious disease and to provoke immunological memory to vaccination. We have discovered that Platelet Endothelial Cell Adhesion Molecule-1 (PECAM-1-CD31) is a new immunoreceptor, that belongs to a very important family of proteins, the Ig-ITIM superfamily which is a subset of the immunoglobulin superfamily. We w ....Immunoreceptors play an important role in balancing the threshold of cellular activation is critical in the immune response to tumours, pathogens or allergens, to arrest autoimmune and infectious disease and to provoke immunological memory to vaccination. We have discovered that Platelet Endothelial Cell Adhesion Molecule-1 (PECAM-1-CD31) is a new immunoreceptor, that belongs to a very important family of proteins, the Ig-ITIM superfamily which is a subset of the immunoglobulin superfamily. We wish to determine if PECAM-1 functions as an inhibitory receptor in the lymphoid microenvironment using genetically engineered mice which lack the protein. As some of the functional features may display modest features, we plan to cross the PECAM-1 deficient mice with hen egg lysozyme transgenic mice to test the importance of PECAM-1 in peripheral tolerance. We will also define its importance in T cell function. We will test if the PECAM-1 deficient mice are more susceptible to the onset of inducible autoimmunde diseases including mouse models of collagen-induced arthritis and diabetes. Finally, we will produce transgenic mice expressing normal and disabled signaling motifs of PECAM-1 to test their requirement in autoimmunity.Read moreRead less
Regulation Of Leukocyte Trafficking By Macrophage Migration Inhibitory Factor (MIF).
Funder
National Health and Medical Research Council
Funding Amount
$239,250.00
Summary
The entry of white blood cells in to tissues is a primary event which drives tissue and organ damage in a number of inflammatory and immune mediated conditions. Diseases as diverse as rheumatoid arthritis, lupus or shock due to bacterial infection (septic shock) have many different triggers and manifestations. However almost all autoimmune and inflammatory diseases have one common feature: white blood cells must leave the blood and enter tissue in order to cause tissue inflammation and ultimatel ....The entry of white blood cells in to tissues is a primary event which drives tissue and organ damage in a number of inflammatory and immune mediated conditions. Diseases as diverse as rheumatoid arthritis, lupus or shock due to bacterial infection (septic shock) have many different triggers and manifestations. However almost all autoimmune and inflammatory diseases have one common feature: white blood cells must leave the blood and enter tissue in order to cause tissue inflammation and ultimately tissue damage and loss of function. The mechanism whereby white blood cells leave the blood stream and cross blood vessel walls to get into tissues is a multi-step process often referred to as white blood cell trafficking. Most of the current treatments for immune and inflammatory conditions have the primary aim of keeping white blood cells out of tissue in order to prevent damage. Some of these treatments, like steroids (cortisone), are very effective but cannot be used for prolonged periods because of the risk of problems like bone thinning (osteoporosis), high blood pressure or diabetes. Other treatments and immunosuppressive agents can also be effective but are themselves associated with toxicity and risk of organ damage. Although substantial progress has been made in the management of immune and inflammatory conditions in the last 50 years, the current treatment options are far from ideal. Macrophage migration inhibitory factor (MIF) is an inflammatory substance released by cells which comprise the blood vessel wall as well as by white blood cells themselves. It is known to contribute to the build up of white blood cells in inflamed tissue. The effect of MIF on white blood cell trafficking has never been examined. Understanding how MIF promotes white cell entry in to tissues could be crucial in our understanding of this important process and blocking MIF may prove to be a useful and effective way to prevent it.Read moreRead less
Regulation Of TNF Receptor Expression By Omega-6 And Omega-3 Polyunsaturated Fatty Acids
Funder
National Health and Medical Research Council
Funding Amount
$226,320.00
Summary
This project looks at two major molecules which our body generates in trying to combat infections, a protein called tumor necrosis factor (TNF) and a fatty acid called arachidonic acid. In some cases the persistent production of elevated amounts of these molecules leads to highly crippling and debilitating diseases , such as rheumatoid arthritis, which pose a huge burden to our community. To develop medication to combat these diseases be it either vaccination or antiinflammatory drugs, there is ....This project looks at two major molecules which our body generates in trying to combat infections, a protein called tumor necrosis factor (TNF) and a fatty acid called arachidonic acid. In some cases the persistent production of elevated amounts of these molecules leads to highly crippling and debilitating diseases , such as rheumatoid arthritis, which pose a huge burden to our community. To develop medication to combat these diseases be it either vaccination or antiinflammatory drugs, there is a need to clearly define key components of the inflammatory response. Since TNF acts through a receptor we propose that a critical issue in the regulation of this inflammatory response is the changes in the expression of these receptors on cells of the immune system. Our preliminary work suggests that lipid molecules such as arachidonic acid (omega-6 fat) interacts with phagocytic cells and causes drammatic changes to the expression of this receptor. Our research proposal will look at this in more detail and place the observation into perspective in terms of parameters of the inflammatory reaction and associated diseases. Furthermore this concept will be examined in relation to the protective effects which the omega-3 fats found in fish oil have on these inflammatory diseases.Read moreRead less
The Role Of PAC-1 In Leukocyte Activation And Inflammatory Responses
Funder
National Health and Medical Research Council
Funding Amount
$465,750.00
Summary
The MAP kinase pathway is fundamental for signalling a variety of cellular responses. This pathway is particularly important for immune responses ie. cytokine signalling, chemotaxis, and proliferation. PAC-1, a MAP kinase phosphatase, is an important regulator of this pathway. Extensive gene profiling of various immune cells using Affymetrix GeneChips identified PAC-1 as a highly regulated molecule in activated mast cells. Mast cells are important inflammatory cells, particularly for rheumatoid ....The MAP kinase pathway is fundamental for signalling a variety of cellular responses. This pathway is particularly important for immune responses ie. cytokine signalling, chemotaxis, and proliferation. PAC-1, a MAP kinase phosphatase, is an important regulator of this pathway. Extensive gene profiling of various immune cells using Affymetrix GeneChips identified PAC-1 as a highly regulated molecule in activated mast cells. Mast cells are important inflammatory cells, particularly for rheumatoid arthritis and asthma. We have shown that PAC-1 deficient mice are highly protected from inflammation and disease in a mouse model of rheumatoid arthritis. This grant aims to extend these exciting initial findings to other inflammatory diseases, particularly asthma and type 1 Diabetes, and to establish the basis for PAC-1 inhibition of disease. This research should establish PAC-1 as a new and important target for inflammatory disease, provide understanding on inflammatory processes, and possibly lead to improved therapies for diseases such as rheumatoid arthritis.Read moreRead less
Leukocyte Immunoglobulin-like Receptors Regulate The Function Of The Major Cells Involved In Allergic Inflammation.
Funder
National Health and Medical Research Council
Funding Amount
$254,250.00
Summary
An important aspect of the immune system is its ability to maintain a delicate equilibrium between the extremes of reactivity and quiescence. A break in this equilibrium can lead to unchecked activation of immune cells or inability of these cells to mount an effective defence. Potential outcomes of the unchecked activation of cells are autoimmune diseases such as rheumatoid arthritis or allergic diseases such as asthma. A new family of cell surface proteins termed leukocyte immunoglobulin-like r ....An important aspect of the immune system is its ability to maintain a delicate equilibrium between the extremes of reactivity and quiescence. A break in this equilibrium can lead to unchecked activation of immune cells or inability of these cells to mount an effective defence. Potential outcomes of the unchecked activation of cells are autoimmune diseases such as rheumatoid arthritis or allergic diseases such as asthma. A new family of cell surface proteins termed leukocyte immunoglobulin-like receptors (LIRs) has been shown to regulate immune cells by either increasing or decreasing their activity. In this project we will study the role of LIRs in regulating the activity of the major cells involved in allergy and asthma. This study would provide important insights to mechanism(s) of regulation of immune cell activation during protective immune responses such as the fight against infections and cancers and during pathological inflammations such as asthma and rheumatoid arthritis. Understanding the role of the LIRs in the regulation of immune cell activation might lead to new therapeutic strategies aimed at restoring the balance between the inhibitory and activating LIRs.Read moreRead less
The In Vivo Biology Of The Novel TGF-b Superfamily Cytokine, MIC-1
Funder
National Health and Medical Research Council
Funding Amount
$280,430.00
Summary
Cytokines are hormone like messengers that mediate the interactions between cells. We have discovered a new cytokine that we have named macrophage inhibitory cytokine 1 (MIC-1). It belongs to a very important familty of proteins that are involved in wound healing, development and inflammation. Our data thus far suggest thatMIC-1 is an antiinflammatory factor that also involved in reproduction, especially in the health of the placenta. To determine the accuracy of these predictions we wish to use ....Cytokines are hormone like messengers that mediate the interactions between cells. We have discovered a new cytokine that we have named macrophage inhibitory cytokine 1 (MIC-1). It belongs to a very important familty of proteins that are involved in wound healing, development and inflammation. Our data thus far suggest thatMIC-1 is an antiinflammatory factor that also involved in reproduction, especially in the health of the placenta. To determine the accuracy of these predictions we wish to use genetic techniques to delete this gene from a mouse. Study of this genetically modified mouse will give us a great deal of information on the most important roles of MIC-1.Read moreRead less