Dataset Information

Comparison of immunoassay- with mass spectrometry-derived p-tau quantification for the detection of Alzheimer's disease pathology.

ABSTRACT:

Background

Antibody-based immunoassays have enabled quantification of very low concentrations of phosphorylated tau (p-tau) protein forms in cerebrospinal fluid (CSF), aiding in the diagnosis of AD. Mass spectrometry enables absolute quantification of multiple p-tau variants within a single run. The goal of this study was to compare the performance of mass spectrometry assessments of p-tau₁₈₁, p-tau₂₁₇ and p-tau₂₃₁ with established immunoassay techniques.

Methods

We measured p-tau₁₈₁, p-tau₂₁₇ and p-tau₂₃₁ concentrations in CSF from 173 participants from the TRIAD cohort and 394 participants from the BioFINDER-2 cohort using both mass spectrometry and immunoassay methods. All subjects were clinically evaluated by dementia specialists and had amyloid-PET and tau-PET assessments. Bland-Altman analyses evaluated the agreement between immunoassay and mass spectrometry p-tau₁₈₁, p-tau₂₁₇ and p-tau₂₃₁. P-tau associations with amyloid-PET and tau-PET uptake were also compared. Receiver Operating Characteristic (ROC) analyses compared the performance of mass spectrometry and immunoassays p-tau concentrations to identify amyloid-PET positivity.

Results

Mass spectrometry and immunoassays of p-tau₂₁₇ were highly comparable in terms of diagnostic performance, between-group effect sizes and associations with PET biomarkers. In contrast, p-tau₁₈₁ and p-tau₂₃₁ concentrations measured using antibody-free mass spectrometry had lower performance compared with immunoassays.

Conclusions

Our results suggest that while similar overall, immunoassay-based p-tau biomarkers are slightly superior to antibody-free mass spectrometry-based p-tau biomarkers. Future work is needed to determine whether the potential to evaluate multiple biomarkers within a single run offsets the slightly lower performance of antibody-free mass spectrometry-based p-tau quantification.

SUBMITTER: Therriault J

PROVIDER: S-EPMC10773025 | biostudies-literature | 2024 Jan

REPOSITORIES: biostudies-literature

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Publications

Comparison of immunoassay- with mass spectrometry-derived p-tau quantification for the detection of Alzheimer's disease pathology.

Therriault Joseph J Woo Marcel S MS Salvadó Gemma G Gobom Johan J Karikari Thomas K TK Janelidze Shorena S Servaes Stijn S Rahmouni Nesrine N Tissot Cécile C Ashton Nicholas J NJ Benedet Andréa Lessa AL Montoliu-Gaya Laia L Macedo Arthur C AC Lussier Firoza Z FZ Stevenson Jenna J Vitali Paolo P Friese Manuel A MA Massarweh Gassan G Soucy Jean-Paul JP Pascoal Tharick A TA Stomrud Erik E Palmqvist Sebastian S Mattsson-Carlgren Niklas N Gauthier Serge S Zetterberg Henrik H Hansson Oskar O Blennow Kaj K Rosa-Neto Pedro P

Molecular neurodegeneration 20240107 1

<h4>Background</h4>Antibody-based immunoassays have enabled quantification of very low concentrations of phosphorylated tau (p-tau) protein forms in cerebrospinal fluid (CSF), aiding in the diagnosis of AD. Mass spectrometry enables absolute quantification of multiple p-tau variants within a single run. The goal of this study was to compare the performance of mass spectrometry assessments of p-tau<sub>181</sub>, p-tau<sub>217</sub> and p-tau<sub>231</sub> with established immunoassay techniques. ...[more]

PMID: 38185677

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Dataset Information

Comparison of immunoassay- with mass spectrometry-derived p-tau quantification for the detection of Alzheimer's disease pathology.

Background

Methods

Results

Conclusions

Publications

Comparison of immunoassay- with mass spectrometry-derived p-tau quantification for the detection of Alzheimer's disease pathology.

Similar Datasets

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