Phosphorylated tau in human cerebrospinal fluid is a diagnostic marker for Alzheimer's disease.
Microtubule-associated protein tau in cerebrospinal fluid (CSF) has been proposed as a diagnostic marker for Alzheimer's disease (AD), but there is overlap between AD patients and non-AD controls. To improve the diagnostic accuracy, we measured phosphorylated tau in CSF, because phosphorylated tau accumulates as pathological paired helical filaments in neurons of the AD brain. Immunoblot showed that CSF contained a 32 kDa N-terminal fragment of tau that was partially phosphorylated on Ser199, Thr231 and Ser235. A sandwich enzyme immunoassay revealed that phosphorylated CSF-tau levels were significantly higher in AD patients than those in non-AD controls. Discrimination between the two groups was clearer in phosphorylated CSF-tau than in total CSF-tau. The data indicate that elevated phosphorylated CSF-tau level is a more specific diagnostic marker for AD.
Ishiguro
K
K
Mitsubishi Kasei Institute of Life Sciences, Machida, Japan. ishiko@libra.ls.m-kagaku.co.jp
Ohno
H
H
Arai
H
H
Yamaguchi
H
H
Urakami
K
K
Park
J M
JM
Sato
K
K
Kohno
H
H
Imahori
K
K
D000544:Alzheimer Disease / Q000134:cerebrospinal fluid* / Q000175:diagnosis*; D015415:Biomarkers / Q000134:cerebrospinal fluid; D006801:Humans; D015151:Immunoblotting; D007124:Immunoenzyme Techniques; D010446:Peptide Fragments / Q000134:cerebrospinal fluid; D010766:Phosphorylation; D012016:Reference Values; D016875:tau Proteins / Q000134:cerebrospinal fluid* / Q000378:metabolism
D015415:Biomarkers; D010446:Peptide Fragments; D016875:tau Proteins