Research Topics
Genomes and Genes | J W SempleSummaryAffiliation: St. Michael's Hospital Country: Canada Publications
| Collaborators
|
Detail Information
Publications
ITP: a new regulatory issue!John W Semple
The Toronto Platelet Immunobiology Group, Toronto, Ontario, Canada
Eur J Haematol 79:279-80. 2007
The immunopathogenesis of immune thrombocytopenia: T cells still take center-stageJohn W Semple
Keenan Research Centre, Li Ka Shing Knowledge Institute of St Michael s Hospital, Department of Pharmacology, University of Toronto, Canadian Blood Services, Ontario, Canada
Curr Opin Hematol 19:357-62. 2012..The purpose of this review is to report on the ITP pathophysiology literature published from January 2011 to early in 2012...
Recent progress in understanding the pathogenesis of immune thrombocytopeniaJohn W Semple
Keenan Research Centre, Li Ka Shing Knowledge Institute of St Michael s Hospital, Department of Pharmacology, University of Toronto, Canadian Blood Services, Toronto, Ontario, Canada
Curr Opin Hematol 17:590-5. 2010..The cause of this platelet-specific autoimmunity remains unknown, but there has been a constant stream of recent publications that suggest ITP is the result of T-cell dysregulation...
Pathogenic T-cell responses in patients with autoimmune thrombocytopenic purpuraJohn W Semple
Department of Laboratory Medicine and Pathobiology, St Michael s Hospital, 30 Bond St, Toronto, Ontario, Canada
J Pediatr Hematol Oncol 25:S11-3. 2003..It will focus on the relationship between T-cell reactivities and cytokine profiles in patients with AITP. Understanding these cellular immune aspects of AITP is vital for developing antigen-specific immunotherapies to treat the disease...
Leucodepletion and immune response mechanismsJ W Semple
Department of Laboratory Medicine and Pathobiology, St. Michael's Hospital, The University of Toronto, Toronto, Canada
Vox Sang 87:136-8. 2004
Autoimmune pathogenesis and autoimmune hemolytic anemiaJohn W Semple
Department of Laboratory Medicine, St Micheal s Hospital, University of Toronto, Ontario, Canada
Semin Hematol 42:122-30. 2005..Both human and animal studies will be discussed. Understanding theses mechanism is vital for developing antigen-specific immunotherapies to treat the disease...
Platelet-bound lipopolysaccharide enhances Fc receptor-mediated phagocytosis of IgG-opsonized plateletsJohn W Semple
Department of Laboratory Medicine, St Michael s Hospital, 30 Bond Street, Toronto, Ontario, Canada
Blood 109:4803-5. 2007....
A novel immunosuppressive pathway involving peroxynitrite-mediated [corrected] nitration of platelet antigens within antigen-presenting cellsJohn W Semple
Keenan Research Centre, Li Ka Shing Knowledge Institute, St Michael s Hospital, Toronto, Ontario, Canada
Transfusion 48:1917-24. 2008..To further analyze this, we focused on NO's major metabolite peroxynitrite (ONOO(-)) and its ability to affect PLT immunity...
Infections, antigen-presenting cells, T cells, and immune tolerance: their role in the pathogenesis of immune thrombocytopeniaJohn W Semple
Keenan Research Centre, Li Ka Shing Knowledge Institute, St Michael s Hospital, 30 Bond Street, Toronto, Ontario M5B 1W8, Canada
Hematol Oncol Clin North Am 23:1177-92. 2009....
Platelets and innate immunityJohn W Semple
Keenan Research Centre, Li Ka Shing Knowledge Institute, St Michael s Hospital, 30 Bond Street, Toronto, ON M5B 1W8, Canada
Cell Mol Life Sci 67:499-511. 2010....
T cell and cytokine abnormalities in patients with autoimmune thrombocytopenic purpuraJohn W Semple
Canadian Blood Services and the Toronto Platelet Immunobiology Group, Ont, Toronto, Canada
Transfus Apher Sci 28:237-42. 2003..Understanding the immune mechanisms controlling cell-mediated mechanisms is vital for developing antigen specific immunotherapies to treat the disease...
Leukoreduction just doesn't "take away" immunogenic leukcocytes, it creates an immunosuppressive leukocyte doseJohn W Semple
Department of Laboratory Medicine and Pathobiology, St. Michael's Hospital, The University of Toronto and The Toronto Platelet Immunobiology Group, Toronto, Ontario, Canada
Vox Sang 83:425-7. 2002
Evaluation of platelet gel characteristics using thrombin produced by the thrombin processing device: a comparative studyElisabeth Semple
Canadian Blood Services, Research and Development, Toronto, Ontario, Canada
J Oral Maxillofac Surg 66:632-8. 2008....
Immune pathophysiology of autoimmune thrombocytopenic purpuraJ W Semple
St Michael s Hospital and the University of Toronto, Toronto, Ontario, Canada
Blood Rev 16:9-12. 2002..Despite this, their exact mechanisms of action remain elusive. This review focuses on cell-mediated and cytokine abnormalities within AITP, and presents data related to the mechanism of action of anti-D...
Recipient antigen-processing pathways of allogeneic platelet antigens: essential mediators of immunityJohn W Semple
Department of Laboratory Medicine and Pathobiology, St. Michael's Hospital, Toronto, Ontario, Canada
Transfusion 42:958-61. 2002
Anti-D (WinRho SD) treatment of children with chronic autoimmune thrombocytopenic purpura stimulates transient cytokine/chemokine productionJ W Semple
Department of Laboratory Medicine and Pathobiology, St Michael s Hospital, Toronoto, Ontario, Canada
Am J Hematol 69:225-7. 2002..It is possible that the induced cytokine/chemokine storm may have an effect on several physiological processes such as those mediating either adverse effects or potentially RES phagocytic activity...
The cellular immunology associated with autoimmune thrombocytopenic purpura: an updateJ W Semple
Division of Haematology, St Michael s Hospital, Ontario, Canada
Transfus Sci 19:245-51. 1998..Understanding these cellular immune responses in AITP may lead to the development of more immune specific therapies for the management of this disease...
A murine model of severe immune thrombocytopenia is induced by antibody- and CD8+ T cell-mediated responses that are differentially sensitive to therapyLeola Chow
Toronto Platelet Immunobiology Group, Toronto, Canada
Blood 115:1247-53. 2010..This novel model not only shows both antibody- and cell-mediated ITP and bleeding but also suggests that these 2 effector mechanisms have a differential response to therapy...
Comparison of platelet immunity in patients with SLE and with ITPA H Lazarus
Division of Immunohaematology, St Michael s Hospital, Toronto, Ont, Canada
Transfus Sci 22:19-27. 2000..While the number of subjects evaluated with SLE-TP was small, these data reveal a number of differences in the immunopathogenesis between SLE-TP and ITP...
Flow cytometric parameters for characterizing platelet activation by measuring P-selectin (CD62) expression: theoretical consideration and evaluation in thrombin-treated platelet populationsV Leytin
Departments of Transfusion Medicine and Laboratory Medicine and Pathobiology, St Michael s Hospital and University of Toronto, Toronto, Canada
Biochem Biophys Res Commun 269:85-90. 2000..Multiparameter analysis of CD62 expression may be useful for selective diagnosis of disorders with systemic or localized platelet activation and for monitoring the clinical course of the disease and effect of therapeutic interventions...
Platelet Toll-like receptor expression modulates lipopolysaccharide-induced thrombocytopenia and tumor necrosis factor-alpha production in vivoRukhsana Aslam
Department of Laboratory Medicine and Pathobiology, St Michael s Hospital, 30 Bond St, Toronto, ON, Canada, M5B 1W8
Blood 107:637-41. 2006..This work implicates platelets as important mediators of innate immune responses against invading microorganisms...
Quantification of platelet activation status by analyzing P-selectin expressionV Leytin
Department of Transfusion Medicine, St Michael s Hospital and University of Toronto, Toronto, Ontario, Canada
Biochem Biophys Res Commun 273:565-70. 2000....
A role for IL-1 receptor antagonist or other cytokines in the acute therapeutic effects of IVIg?Andrew R Crow
Canadian Blood Services, Department of Laboratory Medicine, St Michael s Hospital, 30 Bond St, Toronto, ON, Canada M5B 1W8
Blood 109:155-8. 2007..This suggests that while IVIg may mediate the release of a variety of cytokines, the cytokines tested do not directly participate in the mechanism of IVIg action...
Immune responsiveness against allogeneic platelet transfusions is determined by the recipient's major histocompatibility complex class II phenotypeEbrahim Sayeh
Department of Laboratory Medicine and Pathobiology, St. Michael's Hospital, Toronto, Ontario, Canada
Transfusion 44:1572-8. 2004..The data suggest that strategies to modify recipient MHC class II presentation of donor PLT antigens would be effective in eliminating PLT alloimmunity...
IgG antiplatelet immunity is dependent on an early innate natural killer cell-derived interferon-gamma response that is regulated by CD8+ T cellsEbrahim Sayeh
Department of Laboratory Medicine and Pathobiology, St Michael s Hospital, University of Toronto, ON, Canada
Blood 103:2705-9. 2004....
IVIg inhibits reticuloendothelial system function and ameliorates murine passive-immune thrombocytopenia independent of anti-idiotype reactivityA R Crow
Transfusion Medicine Research and the Department of Laboratory Medicine and Pathobiology, St. Michael's Hospital, Toronto, Canada
Br J Haematol 115:679-86. 2001..Our data suggest that IVIg exerts its rapid effect by inhibiting RES function and that anti-idiotype interactions are not required...
Quality of thrombin produced from the patient's own plasma using the TPD, a new Thrombin-processing DeviceElisabeth Semple
Thermogenesis Corp, Rancho Cordova, California, USA
J Extra Corpor Technol 37:196-200. 2005..TPD-produced thrombin from human plasma has consistent activity and significantly activates platelets and, thus, may have attractive applications such as the production of autologous thrombin for surgical patients...
A novel murine model of fetal and neonatal alloimmune thrombocytopenia: response to intravenous IgG therapyHeyu Ni
Canadian Blood Services and Dept of Laboratory Medicine and Pathobiology, St Michael s Hospital, University of Toronto, 30 Bond St Rm 2 006, Bond Wing, Toronto, ON, Canada M5B 1W8
Blood 107:2976-83. 2006..Furthermore, maternal administration of intravenous immunoglobulin G (IgG) ameliorated FNAITP and down-regulated pathogenic antibodies in both the maternal and fetal circulations...
Intravenous immunoglobulin inhibits anti-glycoprotein IIb-induced platelet apoptosis in a murine model of immune thrombocytopeniaValery Leytin
Division of Transfusion Medicine, Department of Laboratory Medicine, St Michael s Hospital, Toronto, ON, Canada
Br J Haematol 133:78-82. 2006....
HLA alloimmunization against platelet transfusions: pathophysiology, significance, prevention and managementKaterina Pavenski
Keenan Research Centre, Li Ka Shing Knowledge Institute, St Michael s Hospital, Toronto, Ontario, Canada
Tissue Antigens 79:237-45. 2012....
Transfusion-related immunomodulation by platelets is dependent on their expression of MHC Class I molecules and is independent of white cellsRukhsana Aslam
Keenan Research Centre, Li Ka Shing Knowledge Institute, St Michael s Hospital Toronto, Canada
Transfusion 48:1778-86. 2008..We designed a murine PLT transfusion model to study whether leukoreduced PLTs mediate TRIM effects...
Anti-D initially stimulates an Fc-dependent leukocyte oxidative burst and subsequently suppresses erythrophagocytosis via interleukin-1 receptor antagonistMalini D Coopamah
Department of Laboratory Medicine and Pathobiology, St Michael's Hospital, 30 Bond St, Toronto, M5B 1W8 ON, Canada
Blood 102:2862-7. 2003..Taken together, these results suggest that at least one mechanism of action of anti-D is via the production of the anti-inflammatory cytokine IL1ra which can negatively regulate the ability of leukocytes to phagocytose opsonized cells...
Cellular immune mechanisms in autoimmune thrombocytopenic purpura: An updateMalini D Coopamah
Department of Laboratory Medicine and Pathobiology, St. Michael's Hospital, Toronto, Ontario Canada
Transfus Med Rev 17:69-80. 2003..Understanding the interaction between these cell-mediated mechanisms is vital for developing antigen specific immunotherapies to treat this autoimmune disease...
Transfusion of antibody-opsonized red blood cells results in a shift in the immune response from the red blood cell to the antibody in a murine modelDavor Brinc
Canadian Blood Services, Canada
Transfusion 50:2016-25. 2010..Although this AMIS effect has been well described with many different types of cells as well as vaccines and insoluble antigens, the mechanisms behind this effect remain unresolved...
Platelet and red blood cell phagocytosis kinetics are differentially controlled by phosphatase activity within mononuclear cellsRukhsana Aslam
Department of Laboratory Medicine, St Michael s Hospital, The Department of Pharmacology, and the Laboratory of Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
Transfusion 47:2161-8. 2007..g., reactive oxygen species) that alter signaling pathways within the phagocyte. To address this, a flow cytometric assay was used to compare the kinetics and signaling pathways responsible for opsonized PLT and RBC phagocytosis...
Gamma-globulins prepared from sera of multiparous women bind anti-HLA antibodies and inhibit an established in vivo human alloimmune responseJohn W Semple
Department of Laboratory Medicine and Pathobiology, St Michael s Hospital, Toronto, Ontario, Canada
Blood 100:1055-9. 2002....
Platelets play a direct role in sepsis-associated endothelial cell deathJohn W Semple
Thromb Haemost 99:249. 2008
Epitope specificity and isotype of monoclonal anti-D antibodies dictate their ability to inhibit phagocytosis of opsonized plateletsMimi Kjaersgaard
Department of Pediatrics, Aarhus University Hospital, Skejby, Denmark
Blood 110:1359-61. 2007..001) inhibit platelet phagocytosis. The results suggest that MoAnti-D epitope specificity and isotypes are critical requirements for optimal inhibition of opsonized platelet phagocytosis...
Plasma-derived biological medicines used to promote haemostasisFrederick A Ofosu
Canadian Blood Services, Department of Pathology and Molecular Medicine, McMaster University, 1200 Main Street West, HSC 3N26, Hamilton, ON, Canada L8N 3Z5
Thromb Haemost 99:851-62. 2008..It also considers approaches employed to minimize infectivity of biological medicines derived from human and animal plasmas and to manage patients who develop antibodies (inhibitors) to clotting factor concentrate infusions...
About the mechanism of action of WinRho SDFJohn W Semple
Transfusion 47:351; author reply 351-2. 2007
Inhibition of xenogeneic GVHD by PEN110 treatment of donor human PBMNCsLoren D Fast
Department of Medicine, Rhode Island Hospital Brown University, Providence 02903, USA
Transfusion 44:282-5. 2004..The limitation of these assays is that the in vivo GVHD response of treated human WBCs has not been tested directly...
Platelets give us many messagesJohn W Semple
Thromb Haemost 90:562-3. 2003
IVIG induces dose-dependent amelioration of ITP in rodent modelsAndrew R Crow
Blood 101:1658-9; author reply 1659. 2003
