CD53 and Alzheimer disease: This is the first time that a biphasic profile of SNAP-25 and Ng has been reported in sporadic AD, but this profile is similar to that of other synaptic proteins (calsyntenin-1, GluR4, neurexin-2A, neurexin-3A, syntaxin-1B and thy-1 cell surface antigen) [13, 41].