Figure 3
From: Secretory phospholipase A2 modified HDL rapidly and potently suppresses platelet activation
sPLA2-HDL inhibits P-selectin expression, GPIIb/IIIa activation and superoxide production in platelets. Platelets were pretreated with vehicle, native HDL (nHDL, 50 µg/mL), sPLA2-HDL-low (50 µg/mL), sPLA2-HDL-high (50 µg/mL), sPLA2 or varespladib. (a) For GPIIb/IIIa activation platelets were stimulated with ADP (3 µM). (b) Surface expression of P-selectin was induced with ADP (3 µM) in the presence of cytochalasin B (5 µg/mL) (c) Superoxide production was induced with 5 µg/mL collagen. (a–c) GPIIb/IIIa activation, P-selectin expression and superoxide production were measured by flow cytometry. Bar graphs on the left represent mean fluorescence intensity (MFI). Results are shown as mean ± SEM (n = 4–6). Representative flow cytometry histograms of platelets pretreated with sPLA2-HDL-high are displayed on the right. Statistical significance was assessed by one-way ANOVA followed by Dunnett’s post hoc test. *p < 0.05, **p < 0.01 versus vehicle-pretreated and (a,b) ADP or (c) collagen-stimulated platelets.
