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Streamlined Subclass-Specific Absolute Quantification of Serum IgG Glycopeptides Using Synthetic Isotope-Labeled Standards.

ABSTRACT: Absolute glycoproteomics quantification has drawn tremendous attention owing to its prospects in biomarker discovery and clinical implementation but is impeded by a general lack of suitable heavy isotope-labeled glycopeptide standards. In this study, we devised a facile chemoenzymatic strategy to synthesize a total of 36 human IgG glycopeptides attached with well-defined glycoforms, including 15 isotope-labeled ones with a mass increment of 6 Da to their native counterparts. Spiking of these standards into human sera enabled simplified, robust, and precise absolute quantification of IgG glycopeptides in a subclass-specific fashion. Additionally, the implementation of the absolute quantification approach revealed subclass-dependent alteration of serum IgG galactosylation and sialylation in colon cancer samples.

SUBMITTER: Wang S

PROVIDER: S-EPMC8715724 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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Streamlined Subclass-Specific Absolute Quantification of Serum IgG Glycopeptides Using Synthetic Isotope-Labeled Standards.

Wang Shuaishuai S Liu Ding D Qu Jingyao J Zhu He H Chen Congcong C Gibbons Christopher C Greenway Harmon H Wang Peng P Bollag Roni J RJ Liu Kebin K Li Lei L

Analytical chemistry 20210225 10

Absolute glycoproteomics quantification has drawn tremendous attention owing to its prospects in biomarker discovery and clinical implementation but is impeded by a general lack of suitable heavy isotope-labeled glycopeptide standards. In this study, we devised a facile chemoenzymatic strategy to synthesize a total of 36 human IgG glycopeptides attached with well-defined glycoforms, including 15 isotope-labeled ones with a mass increment of 6 Da to their native counterparts. Spiking of these sta ...[more]

PMID: 33630567

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