THE IMMUNOREGULATORY GLYCAN-BINDING PROTEIN GALECTIN-1 TRIGGERS HUMAN PLATELET ACTIVATION

NATALIA PACIENZA; ROBERTO G POZNER; GERMAN A. BIANCO; LINA PAOLA D'ATRI; DIEGO O. CROCI; SOLEDAD NEGROTTO; ELISA MALAVER; RICARDO M. GÓMEZ; GABRIEL RABINOVICH*; MIRTA SCHATTNER* (*MS AND GAR COMPARTEN LA ÚLTIMA AUTORÍA)

FASEB JOURNAL

Federation of American Societies for Experimental Biology

Lugar: Bethesda; Año: 2008 vol. 22 p. 1113 - 1123

0892-6638

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. 22(4):1113-23. Epub 2007 Nov 5.