Understanding The Role Of Chemokine Receptor Modulation In T Cell Trafficking
Funder
National Health and Medical Research Council
Funding Amount
$391,650.00
Summary
This research will begin to determine the significance of changes in the amount of recently-discovered proteins on the surface of cells called T lymphocytes. These cells control immune responses and move throughout the body to do this. Sometimes, they are activated inappropriately and cause diseases like asthma, arthritis and multiple sclerosis. It is therfore important to understand how the movement of these cells through the body is controlled. A better understanding of this process shuld allo ....This research will begin to determine the significance of changes in the amount of recently-discovered proteins on the surface of cells called T lymphocytes. These cells control immune responses and move throughout the body to do this. Sometimes, they are activated inappropriately and cause diseases like asthma, arthritis and multiple sclerosis. It is therfore important to understand how the movement of these cells through the body is controlled. A better understanding of this process shuld allow us to design better ways to control it, thereby controlling the negative aspects of T cell activation.Read moreRead less
Membrane TNF And Lymphotoxin Control Of Chemokine Induction And Inflammation In Tuberculosis
Funder
National Health and Medical Research Council
Funding Amount
$457,500.00
Summary
Tuberculosis (TB) remains an enormous problem worldwide. Most TB is not due to disease at the time of infection, but is a reactivation of dormant disease in people who have never completely eradicated the organisms. Macrophages containing dormant TB organisms are located in lesions called granulomas. Granulomas consist of TB-infected macrophages surrounded by T lymphocytes that actively contain the infection. T lymphocytes prevent the growth of TB organisms in the macrophages and so prevent wide ....Tuberculosis (TB) remains an enormous problem worldwide. Most TB is not due to disease at the time of infection, but is a reactivation of dormant disease in people who have never completely eradicated the organisms. Macrophages containing dormant TB organisms are located in lesions called granulomas. Granulomas consist of TB-infected macrophages surrounded by T lymphocytes that actively contain the infection. T lymphocytes prevent the growth of TB organisms in the macrophages and so prevent widespread infection that would cause illness in the host. Activated T lymphocytes that recognise TB-infected macrophages circulate in blood, are recruited from blood capillaries into the lung, migrate through the tissue and co-localise with infected macrophages. Soluble molecules (cytokines and chemokines) are known to provide the signals that direct cell migration and activation events. This study will investigate in detail cytokines and chemokines that are involved, the cells that produce then and where these cells are located in the lung. We recently showed that tumour necrosis factor (TNF), and the related cytokine lymphotoxin (LT), are essential for lymphocyte migration through the lung. These belong to a family of related molecules that signal through the same panel of receptors and regulate chemokine expression and inflammation. In this study we will use genetically manipulated mice that lack TNF. LT or other family members or that express only membrane-bound TNF to study how each affects production of different chemokines, chemokine receptors and other molecules. Since there are at least 50 known chemokines and 17 chemokine receptors we will use microarray technology to simultaneously screen changes in expression of several thousand genes and laser microdissection to study cells from different location in infected lungs. Understanding signals necessary to direct T cells into granulomas may facilitate new treatments to prevent TB reactivation disease.Read moreRead less
Mechanisms Of Cartilage Destruction And The Effects Of Treatment In Rheumatoid Arthritis
Funder
National Health and Medical Research Council
Funding Amount
$239,830.00
Summary
Rheumatoid arthritis occurs in 1-3% of the population. It is associated with damage to joints causing pain and dificulty with mobility. There are several treatments for rheumatoid arthritis, none of which completely prevents this damage. This study looks at joint tissue and the ways in which damage occurs. It tries to understand why treatment works in some patients and not others. By doing this, the best ways of stopping joint damage will be determined. The study will also tell us the best ways ....Rheumatoid arthritis occurs in 1-3% of the population. It is associated with damage to joints causing pain and dificulty with mobility. There are several treatments for rheumatoid arthritis, none of which completely prevents this damage. This study looks at joint tissue and the ways in which damage occurs. It tries to understand why treatment works in some patients and not others. By doing this, the best ways of stopping joint damage will be determined. The study will also tell us the best ways of looking at whether treatment is working before joint damage occurs.Read moreRead less
Roles Of CD8-positive T Cells And Chemokines In Cerebral Malaria.
Funder
National Health and Medical Research Council
Funding Amount
$392,545.00
Summary
About 2 million people die each year from complications of malaria infection. The most common form of these fatal complications is called cerebral malaria. For reasons that are not fully understood, the brain of the patient becomes affected. Early after infection there are behavioural changes, progressing to coma. About 20% of people who enter coma with malaria infection, and are treated with anti-malarial drugs, die and the remainder recover, sometimes with slight neurological impairment. One t ....About 2 million people die each year from complications of malaria infection. The most common form of these fatal complications is called cerebral malaria. For reasons that are not fully understood, the brain of the patient becomes affected. Early after infection there are behavioural changes, progressing to coma. About 20% of people who enter coma with malaria infection, and are treated with anti-malarial drugs, die and the remainder recover, sometimes with slight neurological impairment. One theory to explain cerebral malaria is that is caused by the body's own immunological response against the parasite. Using an experimental model in mice, we will find out whether the immune system cells called CD8-positive T lymphocytes are important in causing the brain complications. We also will find out whether messenger molecules called chemokines are important. From this work we hope to discover better ways of treating cerebral malaria.Read moreRead less
The Role Of CXCR3 Chemokines In Hepatitis C And Other Forms Of Viral Hepatitis
Funder
National Health and Medical Research Council
Funding Amount
$457,267.00
Summary
The majority of individuals infected with hepatitis C virus (HCV) show a slow progression of liver disease over a period of 10-20 years. This liver disease is primarily a result of the host immune response to liver cells (hepatocytes) infected with HCV. As part of this immune response there in an increase in the number of immune cells that infiltrate the liver. To date we do not fully understand the mechanims that attract these cells to the liver but a class of molecules called chemokines is the ....The majority of individuals infected with hepatitis C virus (HCV) show a slow progression of liver disease over a period of 10-20 years. This liver disease is primarily a result of the host immune response to liver cells (hepatocytes) infected with HCV. As part of this immune response there in an increase in the number of immune cells that infiltrate the liver. To date we do not fully understand the mechanims that attract these cells to the liver but a class of molecules called chemokines is the most likely candidate. Thus a greater understanding of the chemokines expressed in the liver, their modulation and role in attracting immune cells to the liver in HCV-related liver disease will help us understand the basic mechanisms of liver disease with the possibility of development of novel therapeutic strategies. In pilot studies we have shown that the chemokine interferon-inducible T cell alpha chemoattractant (I-TAC) is significantly increased in the liver of persons infected with HCV. I-TAC is a member of the CXCR3 ligand chemokine family that attracts lymphocytes to sites of inflammation and as such may play an important role in hepatitis C. We have also shown that hepatocytes express I-TAC and that HCV can upregulate expression of I-TAC in a laboratory model of HCV replication. This proposal plans to determine the molecular mechanisms of I-TAC expression in response to HCV replication and to investigate if I-TAC expression is unique for hepatits C or a general feature of viral infections of the liver. We also plan to determine the the role of I-TAC and other CXCR3 ligand family members in a mouse model of viral hepatitis through the use of CXCR3 ligand antagonists. These experiments will enhance or knowledge of the role of the CXCR3 ligands in hepatitis C and viral hepatitis in general.Read moreRead less
Cell Migration And Granuloma Formation In The Expression Of Protective Immunity Against Tuberculosis In The Lung
Funder
National Health and Medical Research Council
Funding Amount
$212,036.00
Summary
Tuberculosis (TB) remains an enormous problem worldwide and a continuing health problem in Australia. Most TB is not due to disease at the time of infection, but is a reactivation of dormant infection in people who have never eradicated the organisms. This study will investigate, in mice, how TB is initially contained within the lungs and how reactivation occurs. All mice infected with TB control the infection initially. T lymphocytes are activated and T cells and macrophages are recruited to th ....Tuberculosis (TB) remains an enormous problem worldwide and a continuing health problem in Australia. Most TB is not due to disease at the time of infection, but is a reactivation of dormant infection in people who have never eradicated the organisms. This study will investigate, in mice, how TB is initially contained within the lungs and how reactivation occurs. All mice infected with TB control the infection initially. T lymphocytes are activated and T cells and macrophages are recruited to the lung, migrate into lung tissue and surround infected lung macrophages forming granulomas. We have identified mice that progress to TB disease early after infection (early progressor strains) and another strain that progresses later (late progressors). In the early progressors, lymphocytes are not as efficiently recruited to the lung and do not form the tight granulomas seen in late progressor strains. We plan to make a detailed comparison of these two strains looking at differences in cell-membrane molecules and the soluble messenger molecules (cytokines and chemokines) that provide the signals that attract cells to the lung and direct them to surround infected lung macrophages. By comparing events in early and late progressor strains we will find which molecules are required for initial and long-term containment, and which events lead to breakdown of granulomas and reactivation of disease. In addition, we recently showed that one cytokine, tumour necrosis factor (TNF), is essential for cell migration through the lung. By comparing normal mice with mice deficient in TNF we will study the downstream effects regulated by TNF, particularly the chemokine messengers that direct cell movement into granulomas. By identifying the molecules and cells required to control TB we plan to design improved vaccines to prevent TB infection and improved treatments to prevent disease reactivation.Read moreRead less
Biological Function Of The Chemokine Receptor 6 Expression On B Cells
Funder
National Health and Medical Research Council
Funding Amount
$241,500.00
Summary
The correct movement of cells is important for the defence of the body against micro-organisms. White blood cells have to arrive quickly at the site of an infection and information about this infection has to be spread. White blood cells that navigate the body are using molecules on their surface termed as receptors which help them to detect the scent of their target. One of these receptors is located on white blood cells that produce antibodies and enables these cells to migrate to appropriate ....The correct movement of cells is important for the defence of the body against micro-organisms. White blood cells have to arrive quickly at the site of an infection and information about this infection has to be spread. White blood cells that navigate the body are using molecules on their surface termed as receptors which help them to detect the scent of their target. One of these receptors is located on white blood cells that produce antibodies and enables these cells to migrate to appropriate tissues . We want to know more about the biological role of this receptor and its functions during the immune response to pathogens. It would be of significant importance to understand the impact of these cell surface receptors in detail because this could open the possibility to new therapies of infectious diseases and chronic inflammation.Read moreRead less
Opioids As A New Therapy For Inflammatory Arthritis: Immunopharmacological Mechanisms
Funder
National Health and Medical Research Council
Funding Amount
$406,527.00
Summary
Arthritis is a chronic inflammatory disorder characterized by joint pain, swelling and stiffness. In fact, 69% of patients present with radiographic erosions and joint space narrowing during the first three years of the disease and it is insufficiently appreciated that patients with rheumatoid arthritis may have a 5-year mortality similar to patients with cardiovascular or neoplastic disease. Prevention of disability and death is the ultimate goal of treatment. However, no cure is yet available. ....Arthritis is a chronic inflammatory disorder characterized by joint pain, swelling and stiffness. In fact, 69% of patients present with radiographic erosions and joint space narrowing during the first three years of the disease and it is insufficiently appreciated that patients with rheumatoid arthritis may have a 5-year mortality similar to patients with cardiovascular or neoplastic disease. Prevention of disability and death is the ultimate goal of treatment. However, no cure is yet available. Instead, current treatment is aimed at relieving symptoms and improving functional performance. There is now a growing recognition that patients with rheumatoid arthritis require more agressive treatment early in the disease, before the development of erosions and deformity. My work has shown for the first time that opioid drugs that act via kappa (k) receptors in the periphery are able to ameliorate the incidence and severity of disease symptoms in rat adjuvant arthritis. Histological and radiological analysis reveals a significant, beneficial effect on joint pathology. The present proposal seeks to build upon this basic information gained in rats into the anti-inflammatory mechanisms of opioid action. I will now apply my expertise to extend this research in animals to human tissues. I am able to combine multiple techniques to carry out a systematic and rigorous study on human synovium from arthritis patients. This work aims to find out why opioids have anti-arthritic actions and might potentially lead to potent, less toxic and less expensive new therapies for arthritis and increase our understanding of the pathogenesis of arthritis.Read moreRead less