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Depletion of highly abundant proteins from human cerebrospinal fluid: a cautionary note.

ABSTRACT: Affinity-based techniques, both for enrichment or depletion of proteins of interest, suffer from unwanted interactions between the bait or matrix material and molecules different from the original target. This effect was quantitatively studied by applying two common procedures for the depletion of albumin/gamma immunoglobulin to human cerebrospinal fluid. Proteins of the depleted and the column-bound fraction were identified by mass spectrometry, employing (18)O labeling for quantitation of their abundance. To different extents, the depletion procedures caused the loss of proteins previously suggested as biomarker candidates for neurological diseases. This is an important phenomenon to consider when quantifying protein levels in biological fluids.

SUBMITTER: Gunther R

PROVIDER: S-EPMC4608131 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Depletion of highly abundant proteins from human cerebrospinal fluid: a cautionary note.

Günther Ramona R Krause Eberhard E Schümann Michael M Blasig Ingolf E IE Haseloff Reiner F RF

Molecular neurodegeneration 20151015

Affinity-based techniques, both for enrichment or depletion of proteins of interest, suffer from unwanted interactions between the bait or matrix material and molecules different from the original target. This effect was quantitatively studied by applying two common procedures for the depletion of albumin/gamma immunoglobulin to human cerebrospinal fluid. Proteins of the depleted and the column-bound fraction were identified by mass spectrometry, employing (18)O labeling for quantitation of thei ...[more]

PMID: 26471478

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Addendum: Digestion and depletion of abundant proteins improves proteomic coverage.

Project description: Not available

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