title: The immunoregulatory glycan-binding protein galectin-1 triggers human platelet activation.
abstract: 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.
authors.affiliation: Hematological Research Institute, National Academy of Medicine, Buenos Aires, Argentina.
authors.forename: Natalia
authors.initials: N
authors.lastname: Pacienza
authors.forename: Roberto G
authors.initials: RG
authors.lastname: Pozner
authors.forename: Germán A
authors.initials: GA
authors.lastname: Bianco
authors.forename: Lina P
authors.initials: LP
authors.lastname: D'Atri
authors.forename: Diego O
authors.initials: DO
authors.lastname: Croci
authors.forename: Soledad
authors.initials: S
authors.lastname: Negrotto
authors.forename: Elisa
authors.initials: E
authors.lastname: Malaver
authors.forename: Ricardo M
authors.initials: RM
authors.lastname: Gómez
authors.forename: Gabriel A
authors.initials: GA
authors.lastname: Rabinovich
authors.forename: Mirta
authors.initials: M
authors.lastname: Schattner
mesh_terms: D000199:Actins / Q000378:metabolism; D000244:Adenosine Diphosphate / Q000378:metabolism; D001665:Binding Sites; D001792:Blood Platelets / Q000502:physiology*; D005434:Flow Cytometry; D037483:Galectin 1 / Q000378:metabolism*; D006801:Humans; D039661:Integrin beta3 / Q000378:metabolism; D007962:Leukocytes / Q000378:metabolism; D018613:Microscopy, Confocal; D019007:P-Selectin / Q000378:metabolism; D015539:Platelet Activation; D010974:Platelet Aggregation / Q000502:physiology; D015398:Signal Transduction
chemical_list: D000199:Actins; D037483:Galectin 1; D039661:Integrin beta3; D019007:P-Selectin; D000244:Adenosine Diphosphate