Regulatory Roles Of Mast Cells In Cutaneous Dermatitis In Vivo
Funder
National Health and Medical Research Council
Funding Amount
$586,965.00
Summary
Allergic conditions that can affect the skin, such as contact dermatitis or eczema are common amongst Australians. Although not life threatening, these common skin conditions can cause considerable physical diability and be expensive to treat. The major focus of our research is to define how dermal mast cells can be modulated to help limit the tissue changes and damage associated with these skin conditions, and ultimately develop improved treatments in the future.
Glycosylation Of Pili In Pathogenic Neisseria: Function In Disease And Potential As A Vaccine Antigen
Funder
National Health and Medical Research Council
Funding Amount
$150,880.00
Summary
Disease caused by Group B Neisseria meningitidis and Neisseria gonorrhoeae remain a significant health problem worldwide. There are currently no vaccines available for either of these bacteria. A surface structure found on these bacteria, called pili, are key in host colonisation and disease. Genetics and structural studies have identified that the protein subunits, which make up pili, are glycosylated - modified by the addition of sugars. The role of glycosylation in the disease process is not ....Disease caused by Group B Neisseria meningitidis and Neisseria gonorrhoeae remain a significant health problem worldwide. There are currently no vaccines available for either of these bacteria. A surface structure found on these bacteria, called pili, are key in host colonisation and disease. Genetics and structural studies have identified that the protein subunits, which make up pili, are glycosylated - modified by the addition of sugars. The role of glycosylation in the disease process is not known. It is possible that the glycosylation of pili is required for attachment to host cells or perhaps in evasion of the immune system. In our current studies, we have identified and analysed a number of genes involved in pili glycosylation, in bacteria which make structre that are know. We have also identified a series of new genes we believe are also involved in glycosylation. Some of these genes are involved in the biosynthesis of unknown structures and are common in bacteria isolated from patients with meningitis. We will identify these stuctures and characterise bacteria in which these genes have been inactivated so that we can examine the role of pili glycosylation in colonisation and disease. This study has the potential to yield important new information about the process of colonisation and disease, and also has the potential to facilitate novel approaches in vaccine development.Read moreRead less
Streptococcus pneumoniae (the pneumococcus) is an important human pathogen, which is responsible for the deaths of millions of children each year in developing countries. The high morbidity and mortality associated with pneumococcal disease is also being exacerbated by the rate at which this organism is acquiring resistance to multiple antibiotics. Existing pneumococcal polysaccharide vaccines are poorly immunogenic in young children and only provide cover against a limited range of serotypes. S ....Streptococcus pneumoniae (the pneumococcus) is an important human pathogen, which is responsible for the deaths of millions of children each year in developing countries. The high morbidity and mortality associated with pneumococcal disease is also being exacerbated by the rate at which this organism is acquiring resistance to multiple antibiotics. Existing pneumococcal polysaccharide vaccines are poorly immunogenic in young children and only provide cover against a limited range of serotypes. Serotype coverage is even lower in the more immunogenic conjugate vaccines currently being developed; these will also be very expensive, thereby limiting their use in developing countries, where the need for effective paediatric vaccines is greatest. Pneumococci produce a variety of proteins which are important in causing disease, but the relative contribution of these factors at each stage of the infection process remain to be determined. Moreover, virtually nothing is known of the mechanism whereby these virulence factors are regulated in response to the external environment of the bacterium. In view of this, we are conducting a comprehensive examination of the mechanisms of pathogenesis of pneumococcal disease, with particular reference to the role of putative virulence proteins. This information is being used to develop cheap and effective vaccines based on pneumococcal protein antigens common to all serotypes.Read moreRead less
Virulence Strategies Of LEE-negative Shiga Toxigenic Escherichia Coli
Funder
National Health and Medical Research Council
Funding Amount
$230,246.00
Summary
Shiga toxigenic Escherichia coli (STEC) are a diverse group of pathogens that cause serious gastrointestinal disease in humans, which can lead to life-threatening complications. This project is aimed at understanding how these bacteria cause disease, and is focused on a subset of STEC strains that are highly virulent and produce a novel cytotoxin. A better understanding of the pathogenic mechanisms of STEC is essential for development of improved therapeutic and preventative strategies.
Pathogenesis And Prevention Of Shiga Toxigenic Escherichia Coli Infections
Funder
National Health and Medical Research Council
Funding Amount
$341,320.00
Summary
Shiga toxin (Stx)-producing strains of Escherichia coli (STEC) are known to cause diarrhoea and haemorrhagic colitis in humans. In a proportion of cases, this leads to potentially fatal systemic complications, such as haemolytic uraemic syndrome (HUS), which is the commonest cause of acute renal failure in children. HUS has a high mortality rate in spite of intensive supportive therapy. Morbidity is also substantial, as permanent renal damage and neurological sequelae occur in a significant prop ....Shiga toxin (Stx)-producing strains of Escherichia coli (STEC) are known to cause diarrhoea and haemorrhagic colitis in humans. In a proportion of cases, this leads to potentially fatal systemic complications, such as haemolytic uraemic syndrome (HUS), which is the commonest cause of acute renal failure in children. HUS has a high mortality rate in spite of intensive supportive therapy. Morbidity is also substantial, as permanent renal damage and neurological sequelae occur in a significant proportion of survivors. Large outbreaks of STEC infection are becoming increasingly common, and highlight the threat to public health posed by these bacteria. The serious systemic complications of STEC disease, as well as much of the intestinal pathology, are directly attributable to Stx. However, pathogenesis is multifactorial and capacity of the bacteria to colonize the gut is a crucial virulence trait. STEC infections can now be diagnosed very early in the course of disease, but currently no effective therapeutic intervention is possible. We are addressing this deficiency by developing a novel therapy for STEC infections based on a genetically modified harmless bacterium capable of binding toxin in the gut. Vaccines capable of preventing transmission of STEC disease in the community are also needed, but development of these demands a full understanding of the mechanisms whereby diverse STEC strains adhere to intestinal epithelium and colonize the human gut. We are therefore also examining the interaction between STEC and gut epithelial cells at the cellular and molecular level, with a view to identifying and assessing the vaccine potential of key determinants of adherence.Read moreRead less
Dissecting the physiology of multipotent mesenchymal stromal cells to develop vaccine candidates for respiratory disease. The project aims to gain an understanding of how a type of adult stem cell inhibits immune responses that cause asthma. The project will produce new stem cell products and facilitate the design of a vaccine for asthma and other respiratory diseases, which would greatly reduce the burden of such conditions.
Novel Compounds For Use As Inhibitors Of Virulence Of Human Pathogens
Funder
National Health and Medical Research Council
Funding Amount
$220,500.00
Summary
There is growing concern over the emergence of multi-drug resistant strains of bacteria which are no longer treatable with the current generation of antibiotics. This highlights the urgent need for development of the next generation of therapeutic agents to supplement or replace the current antibiotics. Our research team has identified a class of compounds which are naturally produced by a marine alga that may be effective in the control of bacterial pathogens. These compounds work by interferin ....There is growing concern over the emergence of multi-drug resistant strains of bacteria which are no longer treatable with the current generation of antibiotics. This highlights the urgent need for development of the next generation of therapeutic agents to supplement or replace the current antibiotics. Our research team has identified a class of compounds which are naturally produced by a marine alga that may be effective in the control of bacterial pathogens. These compounds work by interfering with the way many pathogens regulate the production of virulence traits. Some bacteria are able to signal members of their population by the specific uptake and recognition, through a receptor protein, of chemical cues they secrete into the environment. Accumulation of these cues or signals triggers expression of the genes that code for the virulence traits. Moreover, one particular class of these signal response proteins has been identified in many pathogens and has been shown to regulate protease production and production of a protective extracellular slime layer called a capsule. If one or more of these traits can be blocked, then the virulence of the bacterium can be reduced. We have preliminary data which demonstrates that the algal compounds do in fact prevent the expression of virulence traits and thus should be useful as new agents for the treatment of disease. The causative agents of cholera and severe gatroenteritis, Vibrio cholerae and V. parahaemolyticus respectively, have one or the other of these virulence traits, but the pathogen Vibrio vulnificus has all three and therefore is an excellent model pathogen. We propose to explore the ability of the algal compounds to specifically shut down expression of virulence factors with a long term aim for the development of these compounds as novel antimicrobial therapies for the post-antibiotic era.Read moreRead less