Journal of Chromatography & Separation Techniques
Open Access

Automated multiplex LC-MS/MS assay for quantifying serum apolipoproteins A-I, B, C-I, C-II, C-III, and E with qualitative apolipoprotein E phenotyping

3^rd International Conference on Mass Spectrometry

October 10-11, 2016 Kuala Lumpur, Malaysia

Christa Cobbaert

Leiden University Medical Center, Netherlands

Scientific Tracks Abstracts: J Chromatogr Sep Tech

Abstract :

Background: Direct and calculated measures of lipoprotein fractions for cardiovascular risk assessment suffer from analytical inaccuracy in certain dyslipidemic and pathological states, most commonly hypertriglyceridemia. LC-MS/MS has proven suitable for multiplexed quantification and phenotyping of apolipoproteins. Objectives: This study was done to develop and provisionally validate an automated assay for quantification of apolipoprotein (apo) A-I, B, C-I, C-II, C-III, and E and simultaneous qualitative assessment of apoE phenotypes. Methods: We used 5 value-assigned human serum pools for external calibration. Serum proteins were denatured, reduced and alkylated according to standard mass spectrometry based proteomics procedures. After trypsin digestion, peptides were analyzed by LC-MS/ MS. For each peptide, we measured 2 transitions. We compared LC-MS/MS results to those obtained by an immunoturbidimetric assay or ELISA. Results: Intra-assay CVs were 2.3%-5.5%, and total CVs were 2.5%-5.9%. The LC-MS/MS assay correlated (R=0.975-0.995) with immunoturbidimetric assays with Conformit�?© Europ�?©enne marking for apoA-I, apoB, apoC-II, apoC-III, and apoE in normotriglyceridemic (n=54) and hypertriglyceridemic (n=46) sera. Results were interchangeable for apoA-I â�?¤3.0 g/L (Deming slope 1.014) and for apoB-100 â�?¤1.8 g/L (Deming slope 1.016) and were traceable to higher-order standards. Conclusions: The multiplex format provided an opportunity for new diagnostic and pathophysiologic insights into types of dyslipidemia and allowed a more personalized approach for diagnosis and treatment of lipid abnormalities.

Biography :

Christa Cobbaert is working as a Professor at the Leids Universitair Medisch Centrum and has researched on Analytical Chemistry and Mass Spectrometry.

Email: c.cobbaert@planet.nl