I am a cell biologist investigating the means by which intracellular compartmentalization of signalling proteins determines signalling outcomes and cell fate. I focus particularly on signals that regulate immune function and cancer progression.
Dendritic cells are a very rare type of white blood cell which play a critical role in the initiation of the immune response. They are of particular interest to scientists interested in vaccination, as for a vaccine to work effectively, the vaccine must be presented to the rest of the immune system by the dendritic cell. It has only recently become apparent that there are several types of dendritic cell, and these different types of dendritic cell vary in their ability to present a vaccine to th ....Dendritic cells are a very rare type of white blood cell which play a critical role in the initiation of the immune response. They are of particular interest to scientists interested in vaccination, as for a vaccine to work effectively, the vaccine must be presented to the rest of the immune system by the dendritic cell. It has only recently become apparent that there are several types of dendritic cell, and these different types of dendritic cell vary in their ability to present a vaccine to the immune system. We have already identified some proteins that are expressed on the surface of only one type of dendritic cell. We will explore the possible use of these proteins as a means of delivering a vaccine to only one type of dendritic cell. This project will also identify new genes that are expressed in some types of dendritic cells but not others. These new genes whose expression does differ amongst the dendritic cells are potential targets for manipulating the immune system and ensuring more efficient vaccination.Read moreRead less
Role Of Tetraspanins In Integrin Function And Leukocyte Migration
Funder
National Health and Medical Research Council
Funding Amount
$419,223.00
Summary
Cell migration is a very important component of the immune system. White blood cells, migrate from tissues to lymph nodes to initiate immune responses, and can migrate from blood to sites of inflammation to fight infection. This grant studies a type of protein called a tetraspanin that we believe controls white blood cell migration. Understanding the precise role of tetraspanins in this process will further our understanding of inflammation in disease processes.
THE CMRF-35 FAMILY OF MOLECULES: GENE STRUCTURE, EXPRESSION AND FUNCTION
Funder
National Health and Medical Research Council
Funding Amount
$367,669.00
Summary
White blood cells are the army which fights invasion by foreign organisms or cancer cells. Their main artillery and communication systems are located on the cell surface as protein molecules. These recognize foreign material and danger signals, and signal into the cell to direct interactions with other cells- soluble molecules in the immune system. We have discovered a new group of molecules called the CMRF-35 family which are found on the surface of different white blood cells. We have characte ....White blood cells are the army which fights invasion by foreign organisms or cancer cells. Their main artillery and communication systems are located on the cell surface as protein molecules. These recognize foreign material and danger signals, and signal into the cell to direct interactions with other cells- soluble molecules in the immune system. We have discovered a new group of molecules called the CMRF-35 family which are found on the surface of different white blood cells. We have characterized two members of the CMRF-35 family by studying the structure of their genes and the cells which express them. These studies will determine if the known CMRF-35 molecules are able to send signals from the cell surface into the cell to activate or inhibit a functional response by cells that express them. We hope to identify the triggers that initiate a signal from CMRF-35 molecules into the cell and whether there are molecules which bind CMRF-35 molecules and then get moved from the surface to inside the cell. Our data suggests that there are other unknown members of this family. We will determine how many members there are in this family by studying the DNA of genes that are related to the known CMRF-35 molecules. This will allow us to charactertize novel molecules that may be important for white cell function. Discovering new white cell surface molecules and determining their function increases our understanding of how the immune response works. If these CMRF-35 molecules represent a large family, it is highly likely that they have important roles in the immune response. By understanding the signals these molecules send to the cell nucleus we may be able to exploit their function to fight disease. For example where the immune system has not recognized cancer cells as dangerous, we might use the activating CMRF-35 molecules to stimulate a response. In the case of auto-immunity we may be able to reduce the responses via inhibitory CMRF-35 molecules.Read moreRead less
The glomerulus is the filtering component of the kidney. In many diseases, it can be the target of an inappropriate inflammatory response. As part of this response, white blood cells accumulate in the glomerulus where they cause damage. The aim of the project is to determine how these white blood cells accumulate in the glomerulus, specifically asking the question, what molecules present on the white blood cells and the glomerular blood vessels are required for this accumulation?
The Interaction Between CD46 And PSD-95/Dlg-4: Roles In Cell Polarisation And CD46 Signalling.
Funder
National Health and Medical Research Council
Funding Amount
$70,000.00
Summary
Immune defence against pathogens is primarily achieved by the activities of a range of blood cells, including T cells. T cells have specialised functions involving direct killing of the pathogen, and recruitment and activation of other immune cells. Many of these functions require the lymphocyte to become polarised, or asymmetric, in order to concentrate the appropriate cellular machinery towards the site of activity. Examples of polarisation in lymphocytes includes (i) the formation of a single ....Immune defence against pathogens is primarily achieved by the activities of a range of blood cells, including T cells. T cells have specialised functions involving direct killing of the pathogen, and recruitment and activation of other immune cells. Many of these functions require the lymphocyte to become polarised, or asymmetric, in order to concentrate the appropriate cellular machinery towards the site of activity. Examples of polarisation in lymphocytes includes (i) the formation of a single protrusion, or uropod, that forms the basis for cell-cell interactions, (ii) the formation of an immune synapse which allows a T cell to recognise a pathogen, and (iii) the direction of the cellular killing machinery towards the target. The process of cell polarisation is best characterised in neurons and epithelial cells, both of which are asymmetric. In each cell type, a major mechanism of regulating polarisation is the expression and targeting of a family of proteins containing regions called PDZ domains. PDZ domains mediate protein-protein interactions and so allow the assembly of large molecular scaffolds which hold proteins in specific cell sites. The loss of cell polarity in some cells is thought to cause uncontrolled proliferation and tumour progression, and some of the PDZ-containing proteins are tumour suppressors. We have identified a PDZ-containing protein that is polarised in T cells, and have evidence that this protein interacts with and controls the polarisation of a cell surface receptor whose functions include the regulation of T cell function and proliferation. The aim of this proposal is to determine the mechanisms and functional consequences of polarisation of these two proteins in T cells, and to determine whether their interaction or polarisation is important for T cell proliferation.Read moreRead less
Immune defence against pathogens is primarily achieved by the activities of a range of blood cells, including T cells. T cells have specialised functions involving direct killing of the pathogen, and recruitment and activation of other immune cells. Many of these functions require the lymphocyte to become polarised, or asymmetric, in order to concentrate the appropriate cellular machinery towards the site of activity. Examples of polarisation in lymphocytes includes (i) the formation of a single ....Immune defence against pathogens is primarily achieved by the activities of a range of blood cells, including T cells. T cells have specialised functions involving direct killing of the pathogen, and recruitment and activation of other immune cells. Many of these functions require the lymphocyte to become polarised, or asymmetric, in order to concentrate the appropriate cellular machinery towards the site of activity. Examples of polarisation in lymphocytes includes (i) the formation of a single protrusion, or uropod, that forms the basis for cell-cell interactions, (ii) the formation of an immune synapse which allows a T cell to recognise a pathogen, and (iii) the direction of the cellular killing machinery towards the target. The process of cell polarisation is best characterised in neurons and epithelial cells, both of which are asymmetric. In each cell type, a major mechanism of regulating polarisation is the expression and targeting of a family of proteins containing regions called PDZ domains. PDZ domains mediate protein-protein interactions and so allow the assembly of large molecular scaffolds which hold proteins in specific cell sites. The loss of cell polarity in some cells is thought to cause uncontrolled proliferation and tumour progression, and some of the PDZ-containing proteins are tumour suppressors. We have identified a PDZ-containing protein that is polarised in T cells, and have evidence that this protein interacts with and controls the polarisation of a cell surface receptor whose functions include the regulation of T cell function and proliferation. The aim of this proposal is to determine the mechanisms and functional consequences of polarisation of these two proteins in T cells, and to determine whether their interaction or polarisation is important for T cell proliferation.Read moreRead less
Adaptation Of Hepatitis C To Host HLA-Restricted Immune Responses In Australian Populations
Funder
National Health and Medical Research Council
Funding Amount
$480,750.00
Summary
Over 200,000 Australians are infected with the Hepatitis C Virus (HCV) and about 11,000 new infections are diagnosed each year. Around 25% of people infected with HCV will clear the virus while for individuals with chronic infection 10 to 20% will develop cirrhosis of the liver within the next 20-40 years. Differences in host genetic factors and viral variants will, in large part, explain the observed heterogeneity in the clinical outcome and course of HCV infection. The basic theory underpinnin ....Over 200,000 Australians are infected with the Hepatitis C Virus (HCV) and about 11,000 new infections are diagnosed each year. Around 25% of people infected with HCV will clear the virus while for individuals with chronic infection 10 to 20% will develop cirrhosis of the liver within the next 20-40 years. Differences in host genetic factors and viral variants will, in large part, explain the observed heterogeneity in the clinical outcome and course of HCV infection. The basic theory underpinning this research is that the evolution of viruses such as HCV and HIV are influenced by the HLA type of the individual (hots), in combination with the ability of the virus to mutate (rid itself of deleterious mutations) to avoid the host's immune challenge (analogous to drug resistance) even at the lesser cost of impairing viral fitness or replication. We have shown that this is dependent on the immune environment that the virus encounters in relation to which HLA alleles are present in the host, therefore the escape is context specific. After transmission to a new host who lacks the same HLA type, the virus eliminates the previously advantageous mutations which could potentially impair viral fitness. The current study will carry out HCV sequencing and HLA typing on approximately 500 people with HCV from multiple Centres in Australia in order to characterise the interaction between the viral and host genetic factors. A customised software programme, Epipop, has been designed to perform sophisticated statistical analyses on the generated data, and has been successfully applied to HIV vaccine design. The results of this study could help explain why some infected individuals can spontaneously clear their infection while others go on to severe liver disease and allow clinicians to anticipate the course of infection in individuals and plan their management accordingly. Furthermore, the results may facilitate the search for optimal therapeutic and vaccination strategies.Read moreRead less