Agonists inducing sCD154 release.

Purified platelets in buffered solution were activated with 10 μM epinephrine, 1 μM PAF, 10 μM ADP, a combination of epinephrine and ADP (10 μM each), 10 μg/mL collagen, or 0.2 U/mL human thrombin. After the aggregation assay, the samples were incubated without stirring for an additional 50 minutes before the concentration of sCD154 was determined in the respective supernatants with an ELISA. Results are shown for aggregation experiments with 2 different donors to demonstrate the observed variability in the response to ADP. The data are representative of 6 independent experiments.