The Role Of Transcription Factors In Regulating The First Round Of Gene Expression In The Early Embryo.
Funder
National Health and Medical Research Council
Funding Amount
$348,931.00
Summary
Assisted reproductive technologies result in a high incidence of multiple births. This is and adverse outcome that requires correction. It stems from the common transfer of several embryos due to the low chance of an individual embryo made by IVF resulting in a baby. This project will determine the normal pattern of gene expression in the embryo and define: (1) how it is adversely changed as a consequence of IVF; and (2) the extent that these changes are a cause of the low embryo viability.
Mechanisms Of P53 Induced Embryopathy After In Vitro Fertilisation.
Funder
National Health and Medical Research Council
Funding Amount
$483,737.00
Summary
Assisted reproductive technologies (ART) cause many embryos not to survive to birth. We have shown that IVF causes increased expression of protein normally involved in stopping cells from dividing. This is a major cause of embryo death after IVF. This project will determine how this protein acts to cause embryonic death and assess strategies to prevent it.
In recent years it has become clear that certain white blood cells called CD8+ T lymphocytes or killer T cells are required to protect people against HIV. Unfortunately, current vaccines that produce or anti-HIV CD8 T cells only produce effective T cells for a short period. In this project we intend to test a novel vaccine vector called a Kunjin replicon, which promises to persistently produce or maintain effective T cells because the vaccine itself persists and continually immunises for extende ....In recent years it has become clear that certain white blood cells called CD8+ T lymphocytes or killer T cells are required to protect people against HIV. Unfortunately, current vaccines that produce or anti-HIV CD8 T cells only produce effective T cells for a short period. In this project we intend to test a novel vaccine vector called a Kunjin replicon, which promises to persistently produce or maintain effective T cells because the vaccine itself persists and continually immunises for extended periods. We intend to test the ability of this vaccine to persist and persistently produce effective CD8 T cells not only systemically in the blood system but also at mucosal surfaces, where HIV usually gains entry during sexual intercourse.Read moreRead less
CTL Avidity As A Determinant Of The Mature, Antigen-specific Immune Repertoire
Funder
National Health and Medical Research Council
Funding Amount
$241,527.00
Summary
Killer T lymphocytes are a diverse population which vary in their ability to recognise infected cells. This study aims to determine whether vaccine dose and frequency impact on the generation of highly sensitive killer T cells. This study will improve our basic knowledge of killer T lymphocyte selection during infection and have application to improved methods of vaccination.
The normal processes of development of the embryo require that the information encoded in chromosomes be reprogrammed soon after fertilization. This process is rather fragile and disturbance of the early embryo can upset it. Recent studies for the chief investigator's provide new understanding of the normal processes of reprogramming. The project will explore and validate the implications of these new discoveries and provide a basis for future alleviation of abnormalities to development.
Improved Vaccines Against Tuberculosis Based On Dendritic Cell Manipulation
Funder
National Health and Medical Research Council
Funding Amount
$257,036.00
Summary
The incidence of tuberculosis (TB) is increasing throughout the world. BCG, the only currently available vaccine is only partially protective and better vaccines are urgently required to help limit the spread of TB. We have recently prepared naked DNA vaccines with the genes for three mycobacterial proteins and found that they partially protected against lung TB in mice. Further improvement is required and this project is to design and test improved DNA vaccines. Vaccines will be more effective ....The incidence of tuberculosis (TB) is increasing throughout the world. BCG, the only currently available vaccine is only partially protective and better vaccines are urgently required to help limit the spread of TB. We have recently prepared naked DNA vaccines with the genes for three mycobacterial proteins and found that they partially protected against lung TB in mice. Further improvement is required and this project is to design and test improved DNA vaccines. Vaccines will be more effective if they generate stronger cellular immune response to mycobacteria. Dendritic cells (DC) are the major cells that present mycobacterial antigens to T lymphocytes and thus stimulate T lymphocytes to generate immune responses that protect against TB. Therefore the aim of this project is to identify ways to manipulate DC to improve their ability to activate protective immunity. We will target membrane molecules on DC to activate the antigen- presenting function of these cells by fusing the genes for mycobacterial proteins to genes either for antibodies to surface molecules on DC or receptors for these molecules. These novel DNA vaccines will be tested for their effects on DC function and their capacity to stimulate the protective pattern of immunity in mice. The cytokine environment at the time of stimulation will be modified by giving the DNA vaccine together with two cytokine-expressing vaccines, to 'push' the T lymphocytes to respond more vigorously. Finally, we shall test whether a combination of the new DNA vaccines and BCG is more effective than BCG at protecting against virulent TB infection.Read moreRead less
Pathogenesis Of Infections With Yersinia Enterocolitica
Funder
National Health and Medical Research Council
Funding Amount
$339,634.00
Summary
Yersinia enterocolitica is a significant cause of food-poisoning, gastroenteritis and abdominal pain which may be mistaken for acute appendicitis. Y. enterocolitica is a heterogenous bacterial species only some strains of which are able to cause disease. Many of the disease-causing strains have readily identifiable virulence determinants which facilitate their detection in clinical microbiological laboratories. By contrast, other types, in particular the biotype 1A strains, lack these determinan ....Yersinia enterocolitica is a significant cause of food-poisoning, gastroenteritis and abdominal pain which may be mistaken for acute appendicitis. Y. enterocolitica is a heterogenous bacterial species only some strains of which are able to cause disease. Many of the disease-causing strains have readily identifiable virulence determinants which facilitate their detection in clinical microbiological laboratories. By contrast, other types, in particular the biotype 1A strains, lack these determinants, although many of them are significantly associated with disease. During the past few years, we have compared biotype 1A strains of Y. enterocolitica obtained from patients with those from non-clinical sources in a number of assays for virulence-associated properties. These studies have shown that clinical isolates differ from non-clinical ones in terms of their ability to (1) invade epithelial cells in vitro and intestinal absorptive cells in vivo, (2) escape from epithelial cells and macrophages they have invaded, (3) resist killing by macrophages, and (4) colonise the intestinal tracts of mice. The aim of the study is to identify the bacterial determinants responsible for these differences between clinical and non-clinical strains of Y. enterocolitica biotype 1A. This will be achieved by using genetic techniques to modify virulent strains of biotype 1A at random and then identify derivatives of these bacteria with altered virulence properties. We shall also use genetic techniques to identify genes that are specifically activated when the bacteria come into contact with animal cells and tissues. The results of this research will provide new insights into the virulence mechanisms of Y. enterocolitica and related bacteria, and will be used to develop diagnostic tests which will allow pathogenic strains to be distinguished from harmless ones.Read moreRead less
Genetic Adaptations Of Mycobacterium Tuberculosis For Intracellular Survival
Funder
National Health and Medical Research Council
Funding Amount
$187,677.00
Summary
Tuberculosis (TB) remains a significant global public health problem and new approaches to its treatment and prevention are urgently needed. The disease is caused by infection with Mycobacterium tuberculosis, a slow growing organism that lives within cells. How it adapts to survive in this intracellular environment is unknown. Recently the complete genome of M. tuberculosis was sequenced and new techniques developed for manipulating its genes. We plan to use these techniques to identify genes th ....Tuberculosis (TB) remains a significant global public health problem and new approaches to its treatment and prevention are urgently needed. The disease is caused by infection with Mycobacterium tuberculosis, a slow growing organism that lives within cells. How it adapts to survive in this intracellular environment is unknown. Recently the complete genome of M. tuberculosis was sequenced and new techniques developed for manipulating its genes. We plan to use these techniques to identify genes that are more active within the cells. Genes are controlled by short sequences of preceding DNA called promoters. If these promoters are randomly placed in front of readily identifiable reporter genes and inserted into a suitable host strain, it is possible to select for those promoters expressed only inside cells and then identify the promoter and its gene by sequence analysis. We plan to use two types of reporter genes. First, we shall place the M. tuberculosis DNA containing promoters before the gene for a naturally fluorescent protein within the M. bovis BCG host strain and then infect macrophages. If the promoters are switched on inside the cell, the macrophages will become green and can be selected and the promoter identified. After several rounds of selection the promoter is isolated and identified. Second, we shall select the promoters by their ability to produce a protein that is on the surface of the bacterium. We will use these intracellular genes to make better vaccines against TB. Genes that enhance intracellular survival may contribute to the virulence of the TB organism. By removing these genes we can make an attenuated organism suitable as a vaccine. We will test for reduced virulence by growth inside cells in mice. We will also use the intracellular promoter to improve the current BCG vaccine. Proteins expressed inside the cell may also be targets for new TB drugs.Read moreRead less