CHS Research Grants for 2015
- Characterization of Common Inherited Platelet Function Disorders
- Understanding Angiodysplasia in von Willebrand Disease: Studies Using BOEC (Blood Outgrowth Endothelial Cells)
- Role of Gfi1b in the formation of platelets and in inherited bleeding disorders
- Thrombin generation assay to evaluate the heparin in hemophilic plasma
Characterization of Common Inherited Platelet Function Disorders
Dr. Catherine Hayward
McMaster University, Ontario
Second year funding
Dr. Guillaume Pare, McMaster University
Dr. Andrew Paterson, Hospital for Sick Children (University of Toronto)
Platelets are small blood cells that help stop bleeding. If platelets don’t work, it causes bleeding. Platelet disorders are a common cause of abnormal bleeding. To improve knowledge and patient care, we are studying why platelets don’t work normally in some families with bleeding problems. Our goal is to find the causes of very common platelet problems and learn more about how they affect health. We will study genes to learn why some people have platelet problems and others don’t. Answering why platelets don't work normally in some families with bleeding problems requires tests on samples from many persons with platelet problems. Our testing will include studying why platelets don't work normally in individuals from families with platelets problems. Knowledge on what causes common platelet disorders will be helpful to improve patient care and develop better tests for these conditions.
Understanding Angiodysplasia in von Willebrand Disease: Studies Using BOEC (Blood Outgrowth Endothelial Cells)
Dr. Paula James
Queen's University, Ontario
Second year funding.
Co-investigator: Dr. Maurice Don, Queen's University
Von Willebrand disease (VWD) is a common, inherited bleeding disorder that causes excessive bleeding from the skin and mucous membranes. Patients experience nosebleeds, heavy menstrual periods, easy bruising and abnormal bleeding after dental work, childbirth and surgery. Bleeding from the GI (gastrointestinal) tract in VWD patients occurs in up to 20% of patients and can be particularly difficult to treat. We do not completely understand what causes angiodysplasia (small vascular malformations like varicose veins on the inside of the bowel), which is a common reason for GI bleeding in VWD patients. This research project will use endothelial cells that can be cultured from blood samples from VWD patients in order to better understand the factors that lead to angiodysplasia. We will also study the effect and mechanisms of available treatments, including concentrates of von Willebrand factor, estrogen, thalidomide and atorvastatin. Our objective is to improve treatment for VWD with GI bleeding from angiodysplasia.
Role of Gfi1b in the formation of platelets and in inherited bleeding disorders
Dr. Tarik Möröy
Institut de recherches cliniques de Montréal (IRCM)
Department of Hematopoiesis and Cancer
First year funding.
Platelets are essential for blood clotting and are formed in the bone marrow by large cells, so-called 'megakaryocytes', which form long protrusions that penetrate into blood vessels, where the shear forces of the blood stream detach small pieces, which form the platelets. Low platelet numbers can be caused by different diseases or can be the result of an inherited disorder that leaves megakaryocytes unable to produce platelets. These heritable diseases are of clinical importance since low platelet numbers can cause excessive bleeding, which can create severe complications for instance during surgery. A better understanding which factors regulate platelet production is therefore needed to develop new treatments for platelet deficiencies. Recently, mutations in a gene called 'Gfi1b' have been identified in patients with a bleeding disorder caused by low platelet numbers. We have generated mice deficient for this gene and have observed that they show most of the typical symptoms of the human disease associated with the mutated Gfi1b, suggesting that the Gfi1b gene is a critical element in platelet formation. We propose therefore to investigate how this gene functions and regulates platelet formation to gain new insight on how to treat patients with bleeding disorders and platelet deficiencies.
Thrombin generation assay to evaluate the heparin in hemophilic plasma
Lab work studentship
Ellen Z.L. Xu
Supervised by Dr. Howard Chan, McMaster University – Hamilton
Hemophilic patients have bleeding tendency. Yet, in certain situations, these patients are also subject to high risk of clotting. Blood thinner (anticoagulant) is used to prevent or treat blood clot. However, anticoagulant treatment in hemophilic patient will further increase the risk of bleeding. In other words, this will be a 'damn if you do, damn if you don't' situation. In the medical literature, the optimal use of anticoagulant in hemophilic patients having clotting disease is not well studied. With this student scholarship, Ellen Xu is going to use an advanced laboratory assay that can evaluate the clotting in real time to evaluate the effects of an anticoagulant that is commonly used to treat hemophilic patients with blood clot problem. Her work will provide important information to guide the safe use of anticoagulants in hemophilic patients.