Dr. John Semple obtained his PhD in Immunology from Queen’s University at Kingston and was a Diabetes Canada Fellow in the Banting and Best Department of Medical Research at the C.H. Best Institute, University of Toronto. He is a Professor in the Departments of Pharmacology, Medicine and Laboratory Medicine and Pathobiology at the University of Toronto and an Adjunct Scientist with Canadian Blood Services.
Dr. Semple’s research is aimed at understanding the cellular immune mechanisms responsible for the generation of IgG antibodies that recognize platelet antigens. These antibodies can lead to clinically significant adverse effects such as autoimmunity causing immune thrombocytopenia (ITP) and alloimmunity causing platelet transfusion refractoriness. In ITP, for example, his laboratory is interested in how platelet antigens are processed and presented by antigen-presenting cells to activate T lymphocytes. In platelet refractoriness, his group studies the pro-inflammatory nature of platelets responsible for adverse reactions during platelet transfusions, particularly how platelet Toll-like receptor expression modulates innate immune mechanisms. His laboratory also studies the recipient immune mechanisms that cause Transfusion Related Acute Lung Injury (TRALI), a serious complication of transfusion.
Professor Semple is the recipient of many awards and a member of several organisations, including the American and European Societies of Hematology, and has delivered over 120 presentations at international meetings. He has served as a reviewer for numerous journals and granting agencies and authored more than 150 papers in the area of platelet immunology.