Active Transport Of Calcium Across Dental Enamel Cells - Testing A New Paradigm
Funder
National Health and Medical Research Council
Funding Amount
$258,000.00
Summary
Dental enamel defects and tooth loss affect over half our population, resulting in substantial suffering and economic costs. It is likely that many enamel defects could be prevented, and replacement teeth made more lifelike, if more was known about the cells responsible for producing enamel. A particular problem is our lack of understanding about how enamel-forming cells avoid overdosing on calcium, which can lead to cellular toxicity. The overall aim of this research is to use the latest cell b ....Dental enamel defects and tooth loss affect over half our population, resulting in substantial suffering and economic costs. It is likely that many enamel defects could be prevented, and replacement teeth made more lifelike, if more was known about the cells responsible for producing enamel. A particular problem is our lack of understanding about how enamel-forming cells avoid overdosing on calcium, which can lead to cellular toxicity. The overall aim of this research is to use the latest cell biology and biochemical techniques to elucidate the mechanisms of calcium handling in enamel cells, with developing teeth from rat as the experimental model. Our focus is on calcium transport mechanisms, a field where past theories were overturned by our recent findings with gene-knockout animals. We will test a new theory that has arisen from our investigations, using drugs and gene-silencing techniques to interfere with the cellular machinery now thought to be crucial for transporting calcium. By providing strong physiological evidence for this new mechanism, our expected results will define specific proteins that might be targeted by drugs and nutrition, and provide important information about how dietary fluoride and caffeine affect enamel quality. These findings would change thinking about how enamel defects can be prevented and provide a solid foundation to the exciting new field of dental bioengineering, whose goal is to coax stem cells to make natural replacement teeth.Read moreRead less
Characterisation Of Notch Asparaginyl Hydroxylation By FIH-1.
Funder
National Health and Medical Research Council
Funding Amount
$307,841.00
Summary
Cells within our body receive numerous signals telling them when to grow, when to turn into another cell type and exactly what type, and even how to respond to situations like low oxygen. These signals and cells response are very important during embryonic development, when these signals cause a single cell to become a complete person, and also in adults. Here in the embryo, and also in adults, stem cells are very important because they can become many different kinds of cells, depending on what ....Cells within our body receive numerous signals telling them when to grow, when to turn into another cell type and exactly what type, and even how to respond to situations like low oxygen. These signals and cells response are very important during embryonic development, when these signals cause a single cell to become a complete person, and also in adults. Here in the embryo, and also in adults, stem cells are very important because they can become many different kinds of cells, depending on what the body needs. When the signals don't work properly, they cause major problems and diseases, from birth defects, to cancer. Notch is an important protein involved in receiving and passing on certain signals, and is found in organisms as diverse as worms and humans. It tells cells, especially stem cells and other similar cells, when and how to change from one type of cell to another. For example, it is very important in the generation of many different types of blood cells from a single precursor cell. Notch has also been implicated in human diseases such as cancer, where signalling goes wrong and cells keep multiplying out of control, and also certain types of heart disease. Another protein, called FIH, is an oxygen sensor that signals to the cell when there is not enough oxygen around. FIH has also been implicated in cancer and heart disease. We have recently found evidence suggesting that FIH can also influence the activity of the Notch proteins. This means that oxygen levels can potentially have an effect on stem cells and other processes controlled by Notch, and may be very important in cancer and other diseases. This project will first confirm the connection between FIH and Notch. There are a number of different Notch proteins, so we will see if this connection works with all of them. It will also try and work out the consequence of this connection is and how important it is. Finally, the likely biological consequences on human diseases, specifically cancer.Read moreRead less
The C-type Lectin, Mincle, Is A Macrophage Receptor For Candida Albicans.
Funder
National Health and Medical Research Council
Funding Amount
$465,210.00
Summary
The yeast Candida albicans is an important opportunistic infection that causes both mucosal and disseminated disease in patients whose innate or adaptive immune responses are impaired Infection and proliferation results in fungal colonisation of the tissues, and a variable degree of tissue damage. The latter is determined both by the virulence properties of the organism and by the genetic makeup of the host. This large, extracellular pathogen is eradicated from the body predominantly by acavenge ....The yeast Candida albicans is an important opportunistic infection that causes both mucosal and disseminated disease in patients whose innate or adaptive immune responses are impaired Infection and proliferation results in fungal colonisation of the tissues, and a variable degree of tissue damage. The latter is determined both by the virulence properties of the organism and by the genetic makeup of the host. This large, extracellular pathogen is eradicated from the body predominantly by acavenger (phagocytic) cells, which are also important in determining the severity of the associated tissue lesions. A phagocytic cell that is central to both innate and adaptive immune responses is the macrophage, which not only takes up and kills the yeast, but also is capable of of killing and digesting it, and presenting the components to cells of the adaptive immune system. This project is based on the postulate that the outcome and severity of infection is determined, at least in part, by the early functional response of the macrophage to the overall virulence properties of the yeast. The response is initiated by interactions with cell-surface receptors, and this study will show that a novel macrophage receptor, Mincle, is an important part of the innate immune response to fungal infections. We have shown that it is associated with differences in susceptibility to yeast infections in inbred mouse strains; it can discriminate between different isolates of the yeast; and it initiates the inflammatory signalling cascade. Our project will define the specific role of this receptor in fungal infection. The results will be important in understanding the basic biology of host resistance, and will offer new opportunities for therapeutic intervention by selectively blocking or modifying different activation pathways.Read moreRead less