Dataset Information

Stability of blood-based biomarkers of Alzheimer's disease over multiple freeze-thaw cycles.

ABSTRACT:

Introduction

Freeze-thaw instability may contribute to preanalytical variation in blood-based biomarker studies. We investigated the effects of up to four freeze-thaw cycles on single molecule array immunoassays of serum neurofilament light chain and plasma total tau, amyloid β 1-40 (Aß₄₀), and Aβ 1-42 (Aβ₄₂).

Methods

Individuals who had peripheral venepuncture during investigation of suspected neurodegenerative disease were recruited. After standardized preprocessing, 200 μL of plasma and serum aliquots were stored at -80°C within 60 minutes. Aliquots underwent one to four freeze-thaw cycles.

Results

There was no significant difference across four freeze-thaw cycles for serum neurofilament light chain (n = 12), plasma total tau (n = 11), or plasma Aβ₄₂ (n = 12). For plasma Aβ₄₀ (n = 14), there were significant median reductions by ratios of .96 and .92 at the third and fourth cycles, respectively.

Discussion

Up to four freeze-thaw cycles do not influence single molecule array blood biomarkers of neurofilament light chain, total tau, or Aβ₄₂, with at most minor reductions in Aβ₄₀.

SUBMITTER: Keshavan A

PROVIDER: S-EPMC6131984 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Publications

Stability of blood-based biomarkers of Alzheimer's disease over multiple freeze-thaw cycles.

Keshavan Ashvini A Heslegrave Amanda A Zetterberg Henrik H Schott Jonathan M JM

Alzheimer's & dementia (Amsterdam, Netherlands) 20180702

<h4>Introduction</h4>Freeze-thaw instability may contribute to preanalytical variation in blood-based biomarker studies. We investigated the effects of up to four freeze-thaw cycles on single molecule array immunoassays of serum neurofilament light chain and plasma total tau, amyloid β 1-40 (Aß<sub>40</sub>), and Aβ 1-42 (Aβ<sub>42</sub>).<h4>Methods</h4>Individuals who had peripheral venepuncture during investigation of suspected neurodegenerative disease were recruited. After standardized prep ...[more]

PMID: 30211292

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Dataset Information

Stability of blood-based biomarkers of Alzheimer's disease over multiple freeze-thaw cycles.

Introduction

Methods

Results

Discussion

Publications

Stability of blood-based biomarkers of Alzheimer's disease over multiple freeze-thaw cycles.

Similar Datasets

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