%0 Journal Article %J J Alzheimers Dis %D 2018 %T Assay of Plasma Phosphorylated Tau Protein (Threonine 181) and Total Tau Protein in Early-Stage Alzheimer's Disease. %A Yang, Che-Chuan %A Chiu, Ming-Jang %A Chen, Ta-Fu %A Chang, Hui-Ling %A Liu, Bing-Hsien %A Yang, Shieh-Yueh %K Aged %K Aged, 80 and over %K Alzheimer Disease %K Amyloid beta-Peptides %K Biomarkers %K Case-Control Studies %K Female %K Humans %K Magnetic Resonance Imaging %K Male %K Middle Aged %K Neuropsychological Tests %K Phosphorylation %K tau Proteins %X

The feasibility of assaying plasma phosphorylated tau protein (threonine 181), denoted p-tau181, using immunomagnetic reduction (IMR) is explored. The reagent for assaying p-tau181 with IMR was synthesized, and its analytic performances were characterized. Seventy-three subjects were recruited. Each participant was examined with neuropsychological tests, magnetic resonance imaging, and IMR assay for plasma p-tau181. Using commercially available IMR kits, the plasma total tau protein (T-tau) of each subject was assayed. The dynamic range for assaying p-tau181 using IMR was 1.96×10-2 pg/ml to 104 pg/ml. There was no significant interference from total tau protein in the assay of p-tau181. The measured concentrations of plasma p-tau181 were 2.46±1.09 pg/ml for healthy controls, 4.41±1.85 pg/ml for MCI due to AD, and 6.14±1.59 pg/ml for very mild AD. Meanwhile, the measured concentrations of plasma T-tau were 18.85±10.16 pg/ml for healthy controls, 32.98±10.18 pg/ml for MCI due to AD, and 37.54±12.29 pg/ml for very mild AD. A significant difference in plasma p-tau181 was observed between healthy controls and MCI due to AD (p < 0.001) and between MCI due to AD and very mild AD (p < 0.001). However, for the plasma T-tau concentration, a significant difference existed only between healthy controls and MCI due to AD (p < 0.001). This implies that the plasma p-tau181 level is correlated more to AD severity than plasma T-tau is. Additionally, p-tau181 was observed as approximately 14% of T-tau in human plasma.

%B J Alzheimers Dis %V 61 %P 1323-1332 %8 2018 %G eng %N 4 %1 http://www.ncbi.nlm.nih.gov/pubmed/29376870?dopt=Abstract %R 10.3233/JAD-170810