Abstract：
BACKGROUND:Cerebrospinal fluid (CSF) tau is a common biomarker for Alzheimer disease (AD). Measurements of tau have historically been performed using immunoassays. Given the molecular diversity of tau in CSF, the selectivity of these immunoassays has often been questioned. Therefore, we aimed to develop an analytically sensitive and selective immunoaffinity liquid chromatography-tandem mass spectrometry (LC-MS/MS) (IA-MS) assay. METHODS:IA-MS sample analysis involved the addition of an internal standard, immunoaffinity purification of tau using a tau monoclonal antibody coupled to magnetic beads, trypsin digestion, and quantification of a surrogate tau peptide by LC-MS/MS using a Waters Trizaic nanoTile ultraperformance LC microfluidic device. Further characterization of tau peptides was performed by full-scan MS using a Thermo Orbitrap LC-MS. CSF samples from a cohort of age-matched controls and patients with AD were analyzed by the IA-MS method as well as a commercially available immunoassay. RESULTS:The IA-MS assay had intra- and interassay imprecision values of 3.2% to 8.1% CV and 7.8% to 18.9% C, respectively, a mean recovery of 106%, and a limit of quantification of 0.25 pmol/L and was able to quantify tau concentrations in all human specimens tested. The IA-MS assay showed a correlation of R(2) = 0.950 against a total-tau immunoassay. In patients with AD, tau was increased approximately 2-fold. CONCLUSIONS:Combining immunoaffinity enrichment with microflow LC-MS/MS analysis is an effective approach for the development of a highly selective assay to measure total tau and, potentially, other posttranslationally modified forms of tau in CSF.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
McAvoy T,Lassman ME,Spellman DS,Ke Z,Howell BJ,Wong O,Zhu L,Tanen M,Struyk A,Laterza OFdoi
10.1373/clinchem.2013.216515subject
Has Abstractpub_date
2014-04-01 00:00:00pages
683-9issue
4eissn
0009-9147issn
1530-8561pii
clinchem.2013.216515journal_volume
60pub_type
杂志文章abstract：BACKGROUND:Reports of the use of multiplex enzyme assay screening for Pompe disease, Fabry disease, Gaucher disease, Niemann-Pick disease types A and B, and Krabbe disease have engendered interest in the use of this assay in newborn screening. We modified the assay for high-throughput use in screening laboratories. ME...
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journal_title：Clinical chemistry
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abstract：BACKGROUND:Gas6 is a vitamin K-dependent antiapoptotic protein that has been implicated in cardiovascular pathophysiology. We report the development and validation of an ELISA for Gas6, and the variation of plasma Gas6 with hormonal status in a study designed to evaluate the effect of oral contraception on plasma marke...
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journal_title：Clinical chemistry
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doi：
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更新日期：1979-09-01 00:00:00
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doi：
更新日期：1986-03-01 00:00:00
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更新日期：1993-09-01 00:00:00
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doi：
更新日期：1994-02-01 00:00:00
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更新日期：1988-11-01 00:00:00
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更新日期：1980-11-01 00:00:00
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更新日期：1992-09-01 00:00:00
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更新日期：1981-08-01 00:00:00
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更新日期：1988-02-01 00:00:00
