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Serum apolipoprotein A-1 quantification by LC-MS with a SILAC internal standard reveals reduced levels in smokers.

ABSTRACT:

Background

Absolute quantification of protein biomarkers such as serum apolipoprotein A1 by both immunoassays and LC-MS can provide misleading results.

Results

Recombinant ApoA-1 internal standard was prepared using stable isotope labeling by amino acids in cell culture with [(13)C6(15)N2]-lysine and [(13)C9(15)N1]-tyrosine in human cells. A stable isotope dilution LC-MS method for serum ApoA-1 was validated and levels analyzed for 50 nonsmokers and 50 smokers.

Conclusion

The concentration of ApoA-1 in nonsmokers was 169.4 mg/dl with an 18.4% reduction to 138.2 mg/dl in smokers. The validated assay will have clinical utility for assessing effects of smoking cessation and therapeutic or dietary interventions in high-risk populations.

SUBMITTER: Wang Q

PROVIDER: S-EPMC4737526 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Serum apolipoprotein A-1 quantification by LC-MS with a SILAC internal standard reveals reduced levels in smokers.

Wang Qingqing Q Zhang Suhong S Guo Lili L Busch Christine M CM Jian Wenying W Weng Naidong N Snyder Nathaniel W NW Rangiah Kannan K Mesaros Clementina C Blair Ian A IA

Bioanalysis 20150922 22

<h4>Background</h4>Absolute quantification of protein biomarkers such as serum apolipoprotein A1 by both immunoassays and LC-MS can provide misleading results.<h4>Results</h4>Recombinant ApoA-1 internal standard was prepared using stable isotope labeling by amino acids in cell culture with [(13)C6(15)N2]-lysine and [(13)C9(15)N1]-tyrosine in human cells. A stable isotope dilution LC-MS method for serum ApoA-1 was validated and levels analyzed for 50 nonsmokers and 50 smokers.<h4>Conclusion</h4>T ...[more]

PMID: 26394123

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