Dataset Information

Plasma lipoproteome in Alzheimer's disease: a proof-of-concept study.

ABSTRACT:

Background

Although total plasma lipoproteome consists of proteins that have shown promises as biomarkers that can identify Alzheimer's disease (AD), effect sizes are modest. The objective of this study is to provide initial proof-of-concept that the plasma lipoproteome more likely differ between AD cases and controls when measured in individual plasma lipoprotein fractions than when measured as total in immunodepleted plasma.

Methods

We first developed a targeted proteomics method based on selected reaction monitoring (SRM) and liquid chromatography and tandem mass spectrometry for measurement of 120 tryptic peptides from 79 proteins that are commonly present in plasma lipoproteins. Then in a proof-of concept case-control study of 5 AD cases and 5 sex- and age-matched controls, we applied the targeted proteomic method and performed relatively quantification of 120 tryptic peptides in plasma lipoprotein fractions (fractionated by sequential gradient ultracentrifugation) and in immunodepleted plasma (of albumin and IgG). Unadjusted p values from two-sample t-tests and overall fold change was used to evaluate a peptide relative difference between AD cases and controls, with lower p values (?1.05 or?ResultsWithin-day and between-days technical precisions (mean %CV [SD] of all SRM transitions) of the targeted proteomic method were 3.95% (2.65) and 9.31% (5.59), respectively. Between-days technical precisions (mean % CV [SD]) of the entire plasma lipoproteomic workflow including plasma lipoprotein fractionation was 27.90% (14.61). Ten tryptic peptides that belonged to 5 proteins in plasma lipoproteins had unadjusted p values??1.05 or?DiscussionThe findings may warrant future studies to investigate plasma lipoproteome when measured in individual plasma lipoprotein fractions for AD diagnosis.

SUBMITTER: Li D

PROVIDER: S-EPMC6147047 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Publications

Plasma lipoproteome in Alzheimer's disease: a proof-of-concept study.

Li Danni D Huang Fangying F Zhao Yingchun Y Villata Peter W PW Griffin Timothy J TJ Zhang Lin L Li Ling L Yu Fang F

Clinical proteomics 20180920

<h4>Background</h4>Although total plasma lipoproteome consists of proteins that have shown promises as biomarkers that can identify Alzheimer's disease (AD), effect sizes are modest. The objective of this study is to provide initial proof-of-concept that the plasma lipoproteome more likely differ between AD cases and controls when measured in individual plasma lipoprotein fractions than when measured as total in immunodepleted plasma.<h4>Methods</h4>We first developed a targeted proteomics metho ...[more]

PMID: 30250409

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Dataset Information

Plasma lipoproteome in Alzheimer's disease: a proof-of-concept study.

Background

Methods

Publications

Plasma lipoproteome in Alzheimer's disease: a proof-of-concept study.

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