The immunoregulatory glycan-binding protein galectin-1 triggers human platelet activation

FASEB J. 2008 Apr;22(4):1113-23. doi: 10.1096/fj.07-9524com. Epub 2007 Nov 5.


Platelet activation is a critical process during inflammation, thrombosis, and cancer. Here, we show that galectin-1, an endogenous lectin with immunoregulatory properties, plays a key role in human platelet activation and function. Galectin-1 binds to human platelets in a carbohydrate-dependent manner and synergizes with ADP or thrombin to induce platelet aggregation and ATP release. Furthermore, galectin-1 induces F-actin polymerization, up-regulation of P-selectin, and GPIIIa expression; promotes shedding of microvesicles; and triggers conformational changes in GPIIb/IIIa. In addition, exposure to this lectin favors the generation of leukocyte-platelet aggregates. A further mechanistic analysis revealed the involvement of Ca(2+) and cyclic nucleotide-dependent pathways in galectin-1-mediated control of platelet activation. Finally, expression of endogenous galectin-1 in human platelets contributes to ADP-induced aggregation. Our study reveals a novel unrecognized role for galectin-1 in the control of platelet physiology with potential implications in thrombosis, inflammation, and metastasis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / metabolism
  • Adenosine Diphosphate / metabolism
  • Binding Sites
  • Blood Platelets / physiology*
  • Flow Cytometry
  • Galectin 1 / metabolism*
  • Humans
  • Integrin beta3 / metabolism
  • Leukocytes / metabolism
  • Microscopy, Confocal
  • P-Selectin / metabolism
  • Platelet Activation*
  • Platelet Aggregation / physiology
  • Signal Transduction


  • Actins
  • Galectin 1
  • Integrin beta3
  • P-Selectin
  • Adenosine Diphosphate