CSF nonphosphorylated Tau as a biomarker for the discrimination of AD from CJD.

Creutzfeldt-Jakob disease and Alzheimer's disease are characterized by the presence of elevated total-Tau cerebrospinal fluid concentrations while the presence of hyperphosphorylated Tau forms in the cerebrospinal fluid is rather a hallmark of Alzheimer's disease. Here we aimed to investigate potential contribution of nonphospho-Tau epitopes (non-P-Tau) in the discrimination between both diseases. Non-P-Tau cerebrospinal fluid concentration was highly increased in Creutzfeldt-Jakob disease (n = 57, 3683 +/- 3599 pg/mL) compared to Alzheimer's disease (n = 41, 148 +/- 219 pg/mL) and neurological controls (n = 56, 62 +/- 40 pg/mL), and significantly improved the proportion of correctly classified patients (99%) compared to that achieved by total-Tau (90%), P-Tau (62%) and 14-3-3 (91%).