Investigate The Role Of PAF And CD40 Ligand In Regulating The Proinflammatory Properties Of Platelets
Funder
National Health and Medical Research Council
Funding Amount
$507,270.00
Summary
The cells of the blood play an important role in maintaining healthy blood vessels. We are interested in two types of blood cells, platelets and leukocytes, which together play a key role in vessel maintenance, by promoting blood clot formation and vessel wall repair following injury. However, while critical for normal blood vessel maintenance, these cells have also been demonstrated to contribute to disease states including atherosclerosis, thrombosis and inflammatory airway diseases. Underlyin ....The cells of the blood play an important role in maintaining healthy blood vessels. We are interested in two types of blood cells, platelets and leukocytes, which together play a key role in vessel maintenance, by promoting blood clot formation and vessel wall repair following injury. However, while critical for normal blood vessel maintenance, these cells have also been demonstrated to contribute to disease states including atherosclerosis, thrombosis and inflammatory airway diseases. Underlying the function of both blood cell types is their ability to stick (or adhere) to each other. However the way in which they coordinate this adhesion is very complex. New information from our laboratory has demonstrated that the sticky behaviour of each cell type is spatially and temporally regulated, and may involve may factors both inside and outside of the cells themselves. Our studies aim to define the key components regulating the 'stickiness' of these blood cells, in order to undertand how they contribute to maintaining healthy vessel walls, but also how their stickiness may also contribute to the promotion of diseased vessels. This information will not only increase our knowledge of the factors that regulate blood clot formation, but may also assist in the development of new therapies to prevent and-or treat vessel disease.Read moreRead less
Investigate Novel Functional Roles For PI 3-kinases In Platelets.
Funder
National Health and Medical Research Council
Funding Amount
$537,215.00
Summary
Platelets are small blood cells which have a well defined role in blood clotting. There is a growing body of evidence that platelets play an important role in a broad range of inflammatory diseases, and we have identified a key role for the platelet PI3K enzyme in controlling the pro-inflammatory function of platelets. This grant will examine the importance of PI3K in health and disease, and examine the potential therapeutic benefits of inhibiting platelet PI3K.
The Anti-thrombotic Potential Of Immunoreceptors In Platelet Thrombus Formation
Funder
National Health and Medical Research Council
Funding Amount
$522,773.00
Summary
Platelets are small cells in the blood stream that play an important role in preventing excessive blood loss at sites of tissue injury by sticking together and forming a haemostatic plug. Excessive platelet clumping in diseased blood vessels can lead to blockages and cause thrombotic diseases such as heart attack and stroke, two of the biggest killers of humans in the western world. In this proposal, we will seek to understand how immunoreceptors expressed on the surface of platelets modulate th ....Platelets are small cells in the blood stream that play an important role in preventing excessive blood loss at sites of tissue injury by sticking together and forming a haemostatic plug. Excessive platelet clumping in diseased blood vessels can lead to blockages and cause thrombotic diseases such as heart attack and stroke, two of the biggest killers of humans in the western world. In this proposal, we will seek to understand how immunoreceptors expressed on the surface of platelets modulate the function of platelet collagen interactions involving collagen GPVI receptor, the low affinity IgG receptor, FcgammaRIIa and the major platelet integrin, integrin alphaIIbbeta3. The aims of this work will define the role of these receptors in platelet aggregation both in cell-based assays and in mouse models of thrombosis. This work could lead to new strategies for therapeutic management of thrombotic disorders.Read moreRead less
Investigating The Link Between Oxidative Stress And Biomechanical Integrin Activation In Diabetes
Funder
National Health and Medical Research Council
Funding Amount
$653,742.00
Summary
Diabetes represents a serious healthcare problem globally. A large proportion of deaths associated with diabetes can be attributed to the development of blood clots in the circulation of the heart and brain (heart attack/stroke). The blood clotting mechanism is ‘hyperactive’ in diabetes, although the reason for this is not well defined. In this proposal we will investigate a new mechanism promoting blood clots, and will investigate innovative approaches to reduce this clotting mechanism.
Regulation Of Receptors That Control Platelet Function Under Shear Stress
Funder
National Health and Medical Research Council
Funding Amount
$507,273.00
Summary
Specialized human blood cells that control blood loss and clotting (platelets) are currently difficult to test in the clinical laboratory, meaning patients are at risk of excessive bleeding or serious clot formation during disease or treatment. The aim of this proposal is to use our new reagents and assays to develop more reliable methods for evaluating relative bleeding or clotting risk in individuals.
Identification Of A Novel Adhesion Mechanism Regulating Platelet-endothelial Interactions.
Funder
National Health and Medical Research Council
Funding Amount
$501,691.00
Summary
Platelets are important blood cells, stopping bleeding in the event of blood vessel injury. However, platelets can also interact with the blood vessel lining (endothelium) to regulate and in some cases promote inflammation. We have identified a new structure platelets use to stick to endothelium, which under disease states (enhanced oxidative stress), can promote inflammation. We will investigate how tractopods form, and examine their role in the setting of elevated oxidative stress and inflamma ....Platelets are important blood cells, stopping bleeding in the event of blood vessel injury. However, platelets can also interact with the blood vessel lining (endothelium) to regulate and in some cases promote inflammation. We have identified a new structure platelets use to stick to endothelium, which under disease states (enhanced oxidative stress), can promote inflammation. We will investigate how tractopods form, and examine their role in the setting of elevated oxidative stress and inflammatory disease.Read moreRead less
Ligand Interactions Of Platelet Glycoprotein Ib-IX-V In Thrombosis
Funder
National Health and Medical Research Council
Funding Amount
$363,098.00
Summary
The transition of circulating blood platelets from a fluid-phase, non-adherent state to an adherent, activated and aggregated state (thrombus formation) is critical in the normal haemostatic response to blood vessel injury and in thrombotic diseases such as heart attack and stroke. One unique platelet receptor, the glycoprotein Ib-IX-V complex, is of particular interest, because it initiates platelet aggregate or thrombus formation at high fluid shear stress in flowing blood, including the patho ....The transition of circulating blood platelets from a fluid-phase, non-adherent state to an adherent, activated and aggregated state (thrombus formation) is critical in the normal haemostatic response to blood vessel injury and in thrombotic diseases such as heart attack and stroke. One unique platelet receptor, the glycoprotein Ib-IX-V complex, is of particular interest, because it initiates platelet aggregate or thrombus formation at high fluid shear stress in flowing blood, including the pathological shear stress that occurs in a sclerotic coronary artery. Our published and preliminary results show how GPIb-dependent interaction of platelets with von Willebrand factor, the major adhesive ligand for GPIb-IX-V, is dependent on the level of shear stress. Using a cross-species (human to canine) homology-swap approach, where human sequence is replaced by the corresponding canine sequence within discrete structural domains, a sequence of GPIb has been identified which becomes increasingly important as hydrodynamic shear stress increases. It is proposed to further define the interactive surface of GPIb that recognizes von Willebrand factor at increasing shear, and to define the relationship between the shear-dependent alteration of GPIb conformation and its ability to interact with other pro-thrombotic or pro-inflammatory binding partners.Read moreRead less
Autoimmune-based thrombocytopenia can be a life-threatening adverse event associated with viral load, surgery, drug therapies or the use of the anticoagulant, heparin. This grant will define mechanisms of anti-platelet antibody-dependent platelet activation and assess shedding of platelet-specific glycoprotein (GP)VI as an immediate consequence of this activation, provide a new strategy for evaluating risk of thrombosis in HIT.
Investigation Of The Proinflammatory Function Of Platelets During Ischaemia-reperfusion Injury
Funder
National Health and Medical Research Council
Funding Amount
$552,720.00
Summary
Platelets are important blood cells that stop bleeding. Platelets also regulate inflammation by modulating the function of white blood cells. Excessive stimulation of white cells by platelets may cause tissue damage relevant to a broad of cardiovascular diseases, including heart disease and stroke. This grant application aims to investigate the precise mechanism by which platelets promote inflammation during a heart attack or stroke.