Higher platelet CD62P (P-selectin) expression, platelet and platelet–leukocyte mixed aggregates were found in AD patients [217]; this evidence contrasts with that of another study showing increased soluble P-selectin levels but no different CD62P expression in resting platelets, as well as lower levels in platelets stimulated by thrombin receptor activating peptide 6 (TRAP-6) [274]. This evidence concerns the gene SELP and Alzheimer disease.