A Congenic Approach To Analysing The Genomic Control Of Innate Immunity In Health And Disease
Funder
National Health and Medical Research Council
Funding Amount
$240,156.00
Summary
In addition to the lymphocytes, which are specialised white cells that can learn to defeat the infections that the body has been previously exposed, the body has a number of other defences. These non-learning systems have been honed by evolution and usually form an effective first-line of defence. This proposal deals with three: complement, and two highly specialised types of white blood cell, the Natural Killer cells and the NKT cells. The project will study mice especially bred to carry differ ....In addition to the lymphocytes, which are specialised white cells that can learn to defeat the infections that the body has been previously exposed, the body has a number of other defences. These non-learning systems have been honed by evolution and usually form an effective first-line of defence. This proposal deals with three: complement, and two highly specialised types of white blood cell, the Natural Killer cells and the NKT cells. The project will study mice especially bred to carry different versions of the genes which control these defences. Particular attention will be paid to their involvement in the autoimmune diseases, type 1 diabetes and lupus.Read moreRead less
Genomic And Functional Analyses Of A Novel Gene Implicated In Type 1 Diabetes
Funder
National Health and Medical Research Council
Funding Amount
$732,439.00
Summary
We have recently discovered a novel gene that contributes to the development of juvenile diabetes. Unfortunately, very little is known about the function of this gene. To better understand how this gene affects the immune system and contributes to disease, we have generated a unique mouse strain that has a dysfunctional copy of this gene. These mice will enable us to characterise this gene and potentially establish a new area of research in diabetes prevention.
Functional Genomic Analysis Of NK And NKT Cell Immune Control Of Autoimmunity
Funder
National Health and Medical Research Council
Funding Amount
$692,040.00
Summary
The major populations of white blood cells responsible for learned immunity to are the B cells, which make antibody against microorganisms like bacteria, and the T cells, which kill virally infected cells and help B cells produce antibody. The T and B cells occasionally attack the body s own tissues, resulting in autoimmune disease. These diseases include type 1 diabetes, lupus, and anaemia, and collectively represent the third commonest cause of morbidity and mortality in humans. The major reas ....The major populations of white blood cells responsible for learned immunity to are the B cells, which make antibody against microorganisms like bacteria, and the T cells, which kill virally infected cells and help B cells produce antibody. The T and B cells occasionally attack the body s own tissues, resulting in autoimmune disease. These diseases include type 1 diabetes, lupus, and anaemia, and collectively represent the third commonest cause of morbidity and mortality in humans. The major reason why autoimmunity occurs is thought to be due to a failure in the mechanisms responsible for controlling such unwanted responses. Two other populations of white blood cells are involved in this regulation, termed NK and NKT cells, each of which release important cell hormones. The current project is designed to test whether defects in NK and NKT cells lead to autoimmune disease. For this purpose a special strain of mice (NOD mice) will be used. The reasons for their selection are: 1) they are highly susceptible to a range of autoimmune diseases including diabetes, lupus and anaemia, and 2) we and others have found that they are deficient in both NK and NKT cells. The proposed experiments are divided into two groups, one designed to characterise the nature of the defects in these cells and the other to identify the genes responsible for them. In this way it should be possible to shed light on the genetic basis of autoimmune diseases in general. The approach to be used involves sophisticated techniques of genetic analysis, which require production of special congenic lines of mice. These mice are like NOD mice but carry in addition to NOD genes genetic regions from a non-autoimmune strain with the potential to correct the defects in NK and NKT cells. In this way, it should be possible to pinpoint the disease susceptibility genes involved in causation of autoimmunity and to work out how they affect NK and NKT cells.Read moreRead less
Physiological Genomic Analysis Of Lvm-1 - A Genetic Locus That Determines Left Ventricular Mass
Funder
National Health and Medical Research Council
Funding Amount
$356,540.00
Summary
As many as one in ten healthy individuals have big hearts. Careful scientific investigation has revealed that the bigger one's heart, the greater the risk of dying from cardiovascular disease. This is true even in the absence of known causes of heart disease. Unlike high blood pressure or cholesterol, the size of the heart is not easily measured and enlargement often goes undetected. We were among the first internationally to discover genetic clues to enlarged hearts. We identified regions on ra ....As many as one in ten healthy individuals have big hearts. Careful scientific investigation has revealed that the bigger one's heart, the greater the risk of dying from cardiovascular disease. This is true even in the absence of known causes of heart disease. Unlike high blood pressure or cholesterol, the size of the heart is not easily measured and enlargement often goes undetected. We were among the first internationally to discover genetic clues to enlarged hearts. We identified regions on rat chromosomes that harbour the gene or genes that influence heart size. The aim of these studies is to identify the exact gene responsible and to understand how that gene produces its effects. The experiments involve testing DNA samples already obtained from many hundreds of rats and breeding animals to study the consequences of the genetic abnormality in greater detail. The experiments are critical steps towards the prevention of big hearts and their complications in humans. In time, genetic tests will offer earlier detection and facilitate targeted and tailored treatments.Read moreRead less
Chronic or extreme reactions to stress can lead to pathological conditions such as long term anxiety states, depression and panic disorders. Stress related disease also contributes to other major health problems such as heart disease and disorders of the immune system. These disease states include some of the major medical problems of our times. This proposal is to define genes which may be involved in stress responsiveness, to further understand and treat stress related disease.
How Does Genetic Variation For Trig Affect Autoimmune Responses Mediated By Toll-like Receptors?
Funder
National Health and Medical Research Council
Funding Amount
$671,114.00
Summary
Juvenile diabetes is an autoimmune disease that affects more than 120,000 Australians. We have recently discovered a novel gene, named Trig, in a genetic study of mice that develop juvenile diabetes similar to children. This research proposal aims to determine the function of Trig in the immune system and how it contributes to the development of autoimmune diseases, such as juvenile diabetes.
The Roles Of Retinoids And Their Receptors In Haemopoiesis
Funder
National Health and Medical Research Council
Funding Amount
$474,750.00
Summary
Haemopoietic stem cells (HSCs) are the most widely studied adult somatic stem cell. HSCs have huge potential, sustaining blood cell production throughout an individual's life. Cancers (leukaemias) and other disorders of the blood are largely treated by transplantation of HSCs. However, due to their rare occurrence, it is often difficult to obtain large numbers of HSCs for transplantation, especially from sources of HSCs such as cord blood. Furthermore, protocols requiring manipulation of HSCs, s ....Haemopoietic stem cells (HSCs) are the most widely studied adult somatic stem cell. HSCs have huge potential, sustaining blood cell production throughout an individual's life. Cancers (leukaemias) and other disorders of the blood are largely treated by transplantation of HSCs. However, due to their rare occurrence, it is often difficult to obtain large numbers of HSCs for transplantation, especially from sources of HSCs such as cord blood. Furthermore, protocols requiring manipulation of HSCs, such as gene therapy, have been largely unsuccessful, in part due to the lack of success in growing HSCs outside of the body. In such situations, therefore, determining culture conditions that would enable us to grow HSCs outside of the body are highly desirable. This application is based on the studies of CIA, who recently made the novel discoveries that the vitamin A derivative, all-trans retinoic acid (ATRA) has different effects in the regulation of blood cell production. ATRA is currently used in the treatment of acute promyelocytic leukaemia, as it enhances the maturation of the leukaemic cells. CIA has demonstrated that ATRA has the opposite effect on HSCs, with recent data strongly suggesting that ATRA induces the expansion of HSCs outside of the body. The studies outlined in this proposal seek to further define the mechanisms involved in these effects of ATRA and other vitamin A derivatives (collectively termed retinoids) in the regulation of blood cell production. The first specific aim will determine how retinoids expand HSCs. The second specific aim will explore the roles of the different RARs in the regulation of blood cell production. These studies have direct clinical relevance in improving protocols for transplantation and gene therapy of HSCs. Furthermore, insight gained into the roles of retinoids in blood cell production may also lead to the improvement of treatments of various types of blood disorders.Read moreRead less
Epilepsy is an important human disease because it causes physical trauma and sudden death in addition to immense social and economic hardship. The genetic basis of a number of epilepsy syndromes has been identified but the precise mechanism whereby mutations produce seizures is unknown. Several mutations in the alpha4 neuronal nicotinic receptor (a4 nAChR) gene have been identified in Autosomal Dominant Nocturnal Frontal Lobe Epilepsy (ADNFLE). This is a rare form of inherited epilepsy character ....Epilepsy is an important human disease because it causes physical trauma and sudden death in addition to immense social and economic hardship. The genetic basis of a number of epilepsy syndromes has been identified but the precise mechanism whereby mutations produce seizures is unknown. Several mutations in the alpha4 neuronal nicotinic receptor (a4 nAChR) gene have been identified in Autosomal Dominant Nocturnal Frontal Lobe Epilepsy (ADNFLE). This is a rare form of inherited epilepsy characterized by the presence of seizures during light sleep. In vitro studies using the human mutated DNA (i.e. DNA containing the genetic defect) have suggested that this mutation results in reduced activity of the receptor. Therefore a mouse in which this gene is destroyed would be relevant in understanding the human disease. We have generated an a4 nAChR knockout (KO) mouse and plan to use the mouse to test the idea that loss of function of the a4 nAChR in vivo is associated with enhanced seizure activity. The KO mice do not have unprovoked seizures but appear to have an increased number of major motor seizures in response to pentylenetetrazole, an agent which is known to cause seizures by blocking the effects of the brain inhibitory molecule GABA. Interestingly, a4 nAChRs are known to control the release of GABA. We therefore propose that our knockout mice have seizures because they tend to under produce GABA. We will also make and analyse a mouse line with the same genetic mutation as patients with ADNFLE. The experiments are aimed at understanding the way that seizures are generated and spread in the brain in these rare forms of epilepsy. The hope is that understanding these mechanisms will help us better understand and therefore treat common forms of epilepsy.Read moreRead less