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
The Role Of The Platelet Glycoprotein Ib Alpha Cytoplasmic Domain In Thrombosis
Funder
National Health and Medical Research Council
Funding Amount
$600,230.00
Summary
Our studies aim to provide a better understanding of the factors that make platelets sticky, because this is important not only for normal blood clot formation but also in the development of harmful blood clots (thrombosis). Improving our understanding of these processes will add significantly to our knowledge of how blood clotting is controlled. This information is relevant to many human diseases including heart attack and stroke and will help us to develop drugs to prevent these diseases.
Investigation Of Activating Signals Transmitted During Platelet Aggregation
Funder
National Health and Medical Research Council
Funding Amount
$267,750.00
Summary
The blood platelet is a specialized adhesive cell that plays a critical role in the normal blood clotting process through its ability to rapidly adhere to sites of vascular damage. Upon injury to a blood vessel, platelets undergo a number of internal signalling process and strucural changes that allow them to rapidly adhere to the area of damage. Following this initial adhesion process, platelet-platelet interactions occur leading to the development of a stable blood clot. Our research studies a ....The blood platelet is a specialized adhesive cell that plays a critical role in the normal blood clotting process through its ability to rapidly adhere to sites of vascular damage. Upon injury to a blood vessel, platelets undergo a number of internal signalling process and strucural changes that allow them to rapidly adhere to the area of damage. Following this initial adhesion process, platelet-platelet interactions occur leading to the development of a stable blood clot. Our research studies are aimed at understanding more closely the factors that regulate platelet-platelet interactions during the course of blood clot formation, since this is an important determinant not only of normal clot formation, but also in the development of harmful blood clots (thrombi) associated with the onset of diseases such as heart attack and stroke. Our particular focus is on the way in which platelets communicate to one another during the course of platelet thrombus development. Particulary, we are interested in the role of calcium as a signal mediating platelet-platelet communication. We believe that the transmission of these calcium signals may be the key signaling mediator of blood clot formation and normal haemostasis.Read moreRead less
Investigation Of Dok2 And Dok1 Adapter Proteins, In The Negative Regulation Of Integrin AIIbb3 Platelet Signalling.
Funder
National Health and Medical Research Council
Funding Amount
$446,831.00
Summary
Blood platelets play a key role in blood clot formation, prevention of bleeding and are the principal elements contributing to thrombosis leading to heart attack and stroke. Numerous studies have defined pathways promoting platelet activity, however less is known about their negative regulation. In this grant we will examine the role for proteins, Dok2 and Dok1, in the negative regulation of platelets, hoping this leads to development of novel therapeutics for prevention of cardiac disease.
Investigation Of Novel Mechanisms Regulating Platelet Reactivity During Haemostasis And Thrombosis
Funder
National Health and Medical Research Council
Funding Amount
$221,210.00
Summary
Platelets are small specialised blood cells that are critical for normal blood clotting and blood vessel repair following injury. We are studying the processes that enable platelets to stick to the site of vessel injury and to each other to form a stable blood clot. These very processes, when unchecked, are responsible for the formation of harmful blood clots in the bloodstream that may block blood vessels in the heart or brain and result in a heart attack or stroke. Many factors control how big ....Platelets are small specialised blood cells that are critical for normal blood clotting and blood vessel repair following injury. We are studying the processes that enable platelets to stick to the site of vessel injury and to each other to form a stable blood clot. These very processes, when unchecked, are responsible for the formation of harmful blood clots in the bloodstream that may block blood vessels in the heart or brain and result in a heart attack or stroke. Many factors control how big and how rapidly a blood clot grows and whether it becomes harmful enough to lead to a heart attack or stroke. One of these factors is the level of platelet 'reactivity' or 'stickiness' . We are working towards a better understanding of how platelet reactivity is regulated and how this dictates the potential of a blood clot to become harmful. This knowledge will not only increase our knowledge of blood clot formation in health and disease, but also help in the development of new therapies for the prevention of heart attack and stroke.Read moreRead less
Formation of clots to prevent blood loss is initiated by the platelet receptors, glycoprotein (GP)Ib-IX-V and GPVI. Unfortunately, there is a gap in our knowledge regarding the events immediately following activation of these receptors and the known downstream signalling. We have identified a novel binding partner for these platelet receptors, which we believe links reactive oxygen species to platelet signalling events. This opens new avenues for therapies to prevent aberrant clotting.