Figure 1.

Galectin-3 directly potentiates platelet function. (A) Platelet aggregation induced by 0.8 μg/mL collagen (upper panel) or 0.8 U/mL thrombin (lower panel) in platelet-rich plasma correlated well with plasma Galectin-3 levels in patients with coronary artery disease. Platelet aggregation was measured in platelet-rich plasma; plasma Galectin-3 concentration was measured using the enzyme-linked immuno sorbent assay kit. Each solid circle represents a single individual (Spearman correlation, n = 182, GraphPad Prism 7). (B–D) Recombinant Galectin-3, in a concentration-dependent manner, potentiated platelet aggregation induced by collagen (B), thrombin (C), or adenosine diphosphate (D), as well as adenosine tri-phosphate release induced by collagen (B) or thrombin (C). Representative results and summary data of four experiments are presented. (E) Representative fluorescence images (phalloidin) showing that Galectin-3 potentiated platelet spreading on immobilized fibrinogen. After preincubation with recombinant Galectin-3 (20 μg/L) for 5 min, platelets from healthy subjects were allowed to spread for the indicated times. Representative results and summary data (see Supplementary material online, Figure S3A) of three experiments are presented. Scale bar = 10 μm. (F) Galectin-3 potentiated clot retraction induced by thrombin. Washed platelets from healthy subjects were preincubated with recombinant Galectin-3 (20 μg/L) for 5 min and then stimulated with thrombin. Representative results and summary data (see Supplementary material online, Figure S3B) of three experiments are presented. Statistical analyses were performed using repeated measures one-way ANOVA followed by Dunnett's multiple comparisons test in (B), (C), and (D). Two-way ANOVA followed by Sidak's multiple comparisons test was performed in (E) and (F). NS, no significance; *P < 0.05; **P < 0.01.