In this study, human platelet was prepared from blood collected from a cognitively normal control case. Cultured platelets were used for AP-S100A7 ligand-binding assay (bottom); parallel study using AP served as control staining (A). B, C, cultured platelets were treated with 100 nM h-S100A7 for 24 hours; parallel platelet cultures treated with vehicle served as controls. B, α -secretase activity in platelet lysates assessed using the α-secretase activity kit (R&D Systems). C, precursor and mature ADAM-10 content assessed by western blot analysis. Inset, representative western blot analysis of precursor and mature ADAM-10 in platelet lysates. B, C, values represent mean±SEM and are shown as percent of control cells; n = 3 independent cultures per group. *P<0.05, two-tailed Student t-test, hr-S100A7 vs. control group.