A Selected Reaction Monitoring (SRM)-Based Method for Absolute Quantification of Aβ38, Aβ40, and Aβ42 in Cerebrospinal Fluid of Alzheimer's Disease Patients and Healthy Controls

Josef Pannee, Erik Portelius, Madalina Oppermann, Alan Atkins, Martin Hornshaw, Ingrid Zegers, Peter Højrup, Lennart Minthon, Oskar Hansson, Henrik Zetterberg, Kaj Blennow, Johan Gobom

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

Cerebrospinal fluid (CSF) biomarkers for Alzheimer's disease (AD) are increasingly used in research centers, clinical trials, and clinical settings. However, their broad-scale use is hampered by lack of standardization across analytical platforms and by interference from binding of amyloid-β (Aβ) to matrix proteins as well as self-aggregation. Here, we report on a matrix effect-resistant method for the measurement of the AD-associated 42 amino acid species of Aβ (Aβ42), together with Aβ40 and Aβ38 in human CSF based on mass spectrometric quantification using selected reaction monitoring (SRM). Samples were prepared by solid-phase extraction and quantification was performed using stable-isotope labeled Aβ peptides as internal standards. The diagnostic performance of the method was evaluated on two independent clinical materials with research volunteers who were cognitively normal and AD patients with mild to moderate dementia. Analytical characteristics of the method include a lower limit of quantification of 62.5 pg/mL for Aβ42 and coefficients of variations below 10%. In a pilot study on AD patients and controls, we verified disease-association with decreased levels of Aβ42 similar to that obtained by ELISA and even better separation was obtained using the Aβ42/Aβ40 ratio. The developed assay is sensitive and is not influenced by matrix effects, enabling absolute quantification of Aβ42, Aβ40, and Aβ38 in CSF, while it retains the ability to distinguish AD patients from controls. We suggest this SRM-based method for Aβ peptide quantification in human CSF valuable for clinical research and trials.
Original languageEnglish
JournalJournal of Alzheimer's Disease
Volume33
Issue number4
Pages (from-to)1021-1032
ISSN1387-2877
DOIs
Publication statusPublished - 2013

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Cerebrospinal Fluid
Alzheimer Disease
Research
Clinical Trials
Peptides
Solid Phase Extraction
Isotopes
Volunteers
Amino Acids
Proteins

Cite this

Pannee, Josef ; Portelius, Erik ; Oppermann, Madalina ; Atkins, Alan ; Hornshaw, Martin ; Zegers, Ingrid ; Højrup, Peter ; Minthon, Lennart ; Hansson, Oskar ; Zetterberg, Henrik ; Blennow, Kaj ; Gobom, Johan. / A Selected Reaction Monitoring (SRM)-Based Method for Absolute Quantification of Aβ38, Aβ40, and Aβ42 in Cerebrospinal Fluid of Alzheimer's Disease Patients and Healthy Controls. In: Journal of Alzheimer's Disease. 2013 ; Vol. 33, No. 4. pp. 1021-1032.
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abstract = "Cerebrospinal fluid (CSF) biomarkers for Alzheimer's disease (AD) are increasingly used in research centers, clinical trials, and clinical settings. However, their broad-scale use is hampered by lack of standardization across analytical platforms and by interference from binding of amyloid-β (Aβ) to matrix proteins as well as self-aggregation. Here, we report on a matrix effect-resistant method for the measurement of the AD-associated 42 amino acid species of Aβ (Aβ42), together with Aβ40 and Aβ38 in human CSF based on mass spectrometric quantification using selected reaction monitoring (SRM). Samples were prepared by solid-phase extraction and quantification was performed using stable-isotope labeled Aβ peptides as internal standards. The diagnostic performance of the method was evaluated on two independent clinical materials with research volunteers who were cognitively normal and AD patients with mild to moderate dementia. Analytical characteristics of the method include a lower limit of quantification of 62.5 pg/mL for Aβ42 and coefficients of variations below 10{\%}. In a pilot study on AD patients and controls, we verified disease-association with decreased levels of Aβ42 similar to that obtained by ELISA and even better separation was obtained using the Aβ42/Aβ40 ratio. The developed assay is sensitive and is not influenced by matrix effects, enabling absolute quantification of Aβ42, Aβ40, and Aβ38 in CSF, while it retains the ability to distinguish AD patients from controls. We suggest this SRM-based method for Aβ peptide quantification in human CSF valuable for clinical research and trials.",
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Pannee, J, Portelius, E, Oppermann, M, Atkins, A, Hornshaw, M, Zegers, I, Højrup, P, Minthon, L, Hansson, O, Zetterberg, H, Blennow, K & Gobom, J 2013, 'A Selected Reaction Monitoring (SRM)-Based Method for Absolute Quantification of Aβ38, Aβ40, and Aβ42 in Cerebrospinal Fluid of Alzheimer's Disease Patients and Healthy Controls', Journal of Alzheimer's Disease, vol. 33, no. 4, pp. 1021-1032. https://doi.org/10.3233/JAD-2012-121471

A Selected Reaction Monitoring (SRM)-Based Method for Absolute Quantification of Aβ38, Aβ40, and Aβ42 in Cerebrospinal Fluid of Alzheimer's Disease Patients and Healthy Controls. / Pannee, Josef; Portelius, Erik; Oppermann, Madalina; Atkins, Alan; Hornshaw, Martin; Zegers, Ingrid; Højrup, Peter; Minthon, Lennart; Hansson, Oskar; Zetterberg, Henrik; Blennow, Kaj; Gobom, Johan.

In: Journal of Alzheimer's Disease, Vol. 33, No. 4, 2013, p. 1021-1032.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - A Selected Reaction Monitoring (SRM)-Based Method for Absolute Quantification of Aβ38, Aβ40, and Aβ42 in Cerebrospinal Fluid of Alzheimer's Disease Patients and Healthy Controls

AU - Pannee, Josef

AU - Portelius, Erik

AU - Oppermann, Madalina

AU - Atkins, Alan

AU - Hornshaw, Martin

AU - Zegers, Ingrid

AU - Højrup, Peter

AU - Minthon, Lennart

AU - Hansson, Oskar

AU - Zetterberg, Henrik

AU - Blennow, Kaj

AU - Gobom, Johan

PY - 2013

Y1 - 2013

N2 - Cerebrospinal fluid (CSF) biomarkers for Alzheimer's disease (AD) are increasingly used in research centers, clinical trials, and clinical settings. However, their broad-scale use is hampered by lack of standardization across analytical platforms and by interference from binding of amyloid-β (Aβ) to matrix proteins as well as self-aggregation. Here, we report on a matrix effect-resistant method for the measurement of the AD-associated 42 amino acid species of Aβ (Aβ42), together with Aβ40 and Aβ38 in human CSF based on mass spectrometric quantification using selected reaction monitoring (SRM). Samples were prepared by solid-phase extraction and quantification was performed using stable-isotope labeled Aβ peptides as internal standards. The diagnostic performance of the method was evaluated on two independent clinical materials with research volunteers who were cognitively normal and AD patients with mild to moderate dementia. Analytical characteristics of the method include a lower limit of quantification of 62.5 pg/mL for Aβ42 and coefficients of variations below 10%. In a pilot study on AD patients and controls, we verified disease-association with decreased levels of Aβ42 similar to that obtained by ELISA and even better separation was obtained using the Aβ42/Aβ40 ratio. The developed assay is sensitive and is not influenced by matrix effects, enabling absolute quantification of Aβ42, Aβ40, and Aβ38 in CSF, while it retains the ability to distinguish AD patients from controls. We suggest this SRM-based method for Aβ peptide quantification in human CSF valuable for clinical research and trials.

AB - Cerebrospinal fluid (CSF) biomarkers for Alzheimer's disease (AD) are increasingly used in research centers, clinical trials, and clinical settings. However, their broad-scale use is hampered by lack of standardization across analytical platforms and by interference from binding of amyloid-β (Aβ) to matrix proteins as well as self-aggregation. Here, we report on a matrix effect-resistant method for the measurement of the AD-associated 42 amino acid species of Aβ (Aβ42), together with Aβ40 and Aβ38 in human CSF based on mass spectrometric quantification using selected reaction monitoring (SRM). Samples were prepared by solid-phase extraction and quantification was performed using stable-isotope labeled Aβ peptides as internal standards. The diagnostic performance of the method was evaluated on two independent clinical materials with research volunteers who were cognitively normal and AD patients with mild to moderate dementia. Analytical characteristics of the method include a lower limit of quantification of 62.5 pg/mL for Aβ42 and coefficients of variations below 10%. In a pilot study on AD patients and controls, we verified disease-association with decreased levels of Aβ42 similar to that obtained by ELISA and even better separation was obtained using the Aβ42/Aβ40 ratio. The developed assay is sensitive and is not influenced by matrix effects, enabling absolute quantification of Aβ42, Aβ40, and Aβ38 in CSF, while it retains the ability to distinguish AD patients from controls. We suggest this SRM-based method for Aβ peptide quantification in human CSF valuable for clinical research and trials.

U2 - 10.3233/JAD-2012-121471

DO - 10.3233/JAD-2012-121471

M3 - Journal article

C2 - 23076076

VL - 33

SP - 1021

EP - 1032

JO - Journal of Alzheimer's Disease

JF - Journal of Alzheimer's Disease

SN - 1387-2877

IS - 4

ER -