Heyu Ni

MD, PhD, MSc



My laboratory currently investigates the role(s) of adhesion molecules (in particular the beta3 integrin and GPIb alpha complexes) involved in clot formation as well as their implications for hemostasis (including bleeding disorders) and thrombotic diseases (ie. heart attack and stroke). The laboratory also studies allo- and autoimmune diseases related to bleeding disorders such as immune thrombocytopenia (ITP) and fetal and neonatal alloimmune thrombocytopenic purpura (FNAIT). These studies have been well funded by both internal and external granting agencies including Canadian Institutes of Health Research (CIHR), Heart and Stroke Foundation of Canada (HSFC), Canadian Blood Services (CBS), Canada Foundation for Innovation (CFI), and National Institutes of Health (NIH, USA), etc. We are currently funded by 3 CIHR grants and several other grants from HSFC and NIH etc.

Platelet physiology and thrombosis: thrombotic diseases such as heart attack and stroke are the leading causes of mortality and mobility worldwide. We established an intravital microscopy thrombosis model at Harvard to study thrombus formation in real time in live mice. Through direct monitoring of platelet adhesion and aggregation in vivo, we were the first to observe that platelet aggregation and thrombus formation still occur in mice lacking both von Willebrand factor (VWF) and fibrinogen (Fg). This surprising discovery challenged the established theory of thrombosis that required VWF and Fg for thrombus formation and suggested that other unidentified molecule(s) may also be involved in thrombosis and hemostasis and may provide novel targets for anti-thrombotic therapies. My team is in the process of identifying these mystery molecules at St. Michael’s Hospital using several state-of-the-art techniques such as proteomics and confocal intravital microscopy.

Platelet immunology and maternal immune response to fetal antigens: my laboratory recently published several important papers in investigation: 1) How ITP mediated by anti-beta3 integrin and anti-GPIb antibodies differ, finding that these two antibody specificities may respond to therapy differently. This has important implications for human ITP and potential screening of patients in order to successfully treat this disease. 2) The first animal model of FNAIT, characterizing the disease and its response to intravenous immunoglobulin G (IVIG) therapy. Currently, the laboratory is studying the molecular and cellular basis for ITP, the maternal immune responses to fetal platelet antigens and the roles of anti-angiogenesis and apoptosis in the patho-progression of FNAIT.

Scientific Memberships:

International Society of Thrombosis and Hemostasis
American Society of Hematology
American Association of Blood Banks
Canadian Society of Atherosclerosis, Thrombosis and Vascular Biology
Canadian Society of Transfusion Medicine

Committee Membership & Grant Reviewer:

Canadian Institutes of Health Research
Natural Sciences and Engineering Research Council of Canada
Canada Foundation for Innovation
Heart and Stroke Foundation of Canada
The Kidney Foundation of Canada
China (NSFC)-Canada (CIHR) Joint Health Research Initiative – Grants Program
Alberta Heritage Foundation for Medical Research
Landsteiner Foundation for Blood Transfusion Research
National Institutes of Health
Medical Research Council, United Kingdom

Award Reviewer:

Canadian Institutes of Health Research Travel Award
Canadian Blood Services Graduate Fellowship
Ontario Graduate Scholarships in Science and Technology
Heart and Stroke/ Richard Lewar Centre of Excellence Fellowship, University of Toronto
Department of Laboratory Medicine and Pathobiology Graduate Award, University of Toronto
St. Michael’s Hosptial graduate scholarship

Journal Reviewer:

Circulation Research
Journal of Clinical Investigation
Journal of Biological Chemistry
Journal of Thrombosis and Haemostasis
Arteriosclerosis, Thrombosis, and Vascular Biology
Thrombosis and Haemostasis
Cellular and Molecular Life Sciences
Journal of Leukocyte Biology
Thrombosis and Hemostasis
Clinical Immunology
Experimental Hematology
European Journal of Hematology
Journal of Natural Products
British Journal of Haematology
Current Medicinal Chemistry
Cardiovascular Pathology

Recent Publications

  1. Neves, MAD, Ni, TT, Mackeigan, DT, Shoara, AA, Lei, X, Slavkovic, S et al.. Salvianolic acid B inhibits thrombosis and directly blocks the thrombin catalytic site. Res Pract Thromb Haemost. 2024;8 (4):102443. doi: 10.1016/j.rpth.2024.102443. PubMed PMID:38993621 PubMed Central PMC11238050.
  2. Chen, YB, Lin, HY, Wang, LJ, Hung, KC, Brunoni, AR, Chou, PH et al.. A network meta-analysis of non-invasive brain stimulation interventions for autism spectrum disorder: Evidence from randomized controlled trials. Neurosci Biobehav Rev. 2024;164 :105807. doi: 10.1016/j.neubiorev.2024.105807. PubMed PMID:38981573 .
  3. Nagrath, M, Rahimnejad Yazdi, A, Marx, D, Ni, T, Gallant, RC, Ni, H et al.. In vitro analysis of tantalum-containing mesoporous bioactive glass fibres for haemostasis. J Med Eng Technol. 2024;48 (1):12-24. doi: 10.1080/03091902.2024.2356618. PubMed PMID:38857023 .
  4. MacKeigan, DT, Yu, SY, Chazot, N, Zhang, D, Khoury, CJ, Lei, X et al.. Apolipoprotein A-IV polymorphisms Q360H and T347S attenuate its endogenous inhibition of thrombosis. Biochem Biophys Res Commun. 2024;712-713 :149946. doi: 10.1016/j.bbrc.2024.149946. PubMed PMID:38643717 .
  5. Karakas, D, Ni, H. Unveiling Platelets as Immune Regulatory Cells. Circ Res. 2024;134 (8):987-989. doi: 10.1161/CIRCRESAHA.124.324167. PubMed PMID:38603477 .
  6. Yeh, CH, Lin, PC, Tseng, RY, Chao, YP, Wu, CT, Chou, TL et al.. Lack of effects of eight-week left dorsolateral prefrontal theta burst stimulation on white matter macro/microstructure and connection in autism. Brain Imaging Behav. 2024; :. doi: 10.1007/s11682-024-00874-x. PubMed PMID:38492129 .
  7. Li, J, Karakas, D, Xue, F, Chen, Y, Zhu, G, Yucel, YH et al.. Desialylated Platelet Clearance in the Liver is a Novel Mechanism of Systemic Immunosuppression. Research (Wash D C). 2023;6 :0236. doi: 10.34133/research.0236. PubMed PMID:37808178 PubMed Central PMC10551749.
  8. Luis, TC, Barkas, N, Carrelha, J, Giustacchini, A, Mazzi, S, Norfo, R et al.. Perivascular niche cells sense thrombocytopenia and activate hematopoietic stem cells in an IL-1 dependent manner. Nat Commun. 2023;14 (1):6062. doi: 10.1038/s41467-023-41691-y. PubMed PMID:37770432 PubMed Central PMC10539537.
  9. Liu, CH, Chen, YL, Chen, PJ, Ni, HC, Lai, MC. Exploring camouflaging by the Chinese version Camouflaging Autistic Traits Questionnaire in Taiwanese autistic and non-autistic adolescents: An initial development. Autism. 2024;28 (3):690-704. doi: 10.1177/13623613231181732. PubMed PMID:37427427 .
  10. Ma, X, Liang, J, Zhu, G, Bhoria, P, Shoara, AA, MacKeigan, DT et al.. SARS-CoV-2 RBD and Its Variants Can Induce Platelet Activation and Clearance: Implications for Antibody Therapy and Vaccinations against COVID-19. Research (Wash D C). 2023;6 :0124. doi: 10.34133/research.0124. PubMed PMID:37223472 PubMed Central PMC10202384.
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Affiliations & Other Activities

  • Scientist, Keenan Research Centre for Biomedical Science, St. Michael’s Hospital
  • Professor, Department of Laboratory Medicine and Pathobiology, University of Toronto
  • Professor, Department of Medicine, University of Toronto
  • Professor, Department of Physiology, University of Toronto
  • Scientist, Canadian Blood Services Centre for Innovovation Platform
  • Director for Hematology, Cancer and Immunological Diseases