Advances in tau biomarkers: CIEN and the University of Gothenburg present a study of plasma biomarkers with postmortem neuropathological confirmation.

The CIEN Foundation, in collaboration with the University of Gothenburg, has published a new article in Alzheimer’s & Dementia that deepens the understanding of plasma tau biomarkers and their relationship to brain pathology in Alzheimer’s disease.

The aim was to assess whether plasma concentrations could predict the load and distribution of histologically confirmed brain pathology.

The study is part of the Vallecas Alzheimer Reina Sofía Project (VARS) and analyzes plasma samples from 102 brain donors, with an average of 143 days between blood collection and death. Measurements were carried out using mass spectrometry to quantify six phosphorylated tau biomarkers and two non-phosphorylated ones.

Key findings include:

• The p-tau217 biomarker showed a strong association with the presence of neurofibrillary tangles in all evaluated brain regions, whereas p-tau205 was mainly linked to the frontal cortex, and the non-phosphorylated forms to the temporal cortex.
• Plasma tau levels were lower in cases with a higher stage of Lewy body pathology, even when they had the same stage of tau pathology (Braak tau stage).
• All biomarkers correlated with creatinine levels, although this effect was largely mitigated when using ratios (phosphorylated/non-phosphorylated).
• The p-tau199 biomarker showed a distinct pattern, with no association to the number of neurofibrillary tangles but significant correlations with brain volume and survival.

This study represents a significant step forward in the validation and accurate interpretation of plasma tau biomarkers, contributing to their future clinical application in the diagnosis and monitoring of Alzheimer’s disease.

At CIEN, we remain committed to cutting-edge research to better understand Alzheimer’s disease and to advance toward more precise biomarkers that facilitate early diagnosis and the development of new therapeutic strategies. This study reinforces our mission to generate knowledge that can be translated into clinical practice.

Reference:

Montoliu-Gaya L., Valeriano-Lorenzo E., Ashton N.J., López-González F.J., Lantero-Rodriguez J., Ruiz-González A., Pastor A.B., Frades B., Zea-Sevilla M.A., Valentí M., Ruiz-Valderrey P., Saiz L., Burgueño-García I., López-Martínez M.J., del Ser T., Brinkmalm G., Zetterberg H., Rábano A., Gobom J., Blennow K., Sánchez-Juan P., et al. (2025). Plasma tau biomarkers are distinctly associated with tau tangles and decreased with Lewy body pathology. Alzheimer’s & Dementia.

Published online August 12, 2025. https://doi.org/10.1002/alz.70562