Dataset Information

Human cTnT fragmentation in serum

ABSTRACT: Cardiac troponin T (cTnT) is a highly cardiospecific protein commonly used in the diagnosis of acute myocardial infarction (AMI), but is subject to proteolytic degradation upon its release in the circulation. In this study, a targeted mass spectrometry assay was developed to detect peptides which are differentially present within the different degradation products. cTnT was spiked in human serum and incubated at 37 °C to induce proteolytic degradation. Isolation and fractionation of cTnT and its fragments from serum were performed using immunoprecipitation and SDS-PAGE. Bands migrating to 37 kDa (intact cTnT), 29 kDa (primary fragment), and 19, 18, and 16 kDa (secondary fragments) were excised, digested, and subsequently analysed using targeted selected ion monitoring on a UHPLC-coupled quadrupole-Orbitrap mass spectrometer. Sixteen precursor ions from a total of 11 peptides unique to cTnT were targeted. Precursor ions were detectable up until 1200 ng/L cTnT, which is a typical cTnT concentration after AMI. With tandem-MS and relative quantification, we proved the formation of cTnT fragments upon incubation in human serum and identified differentially present peptides in the fragment bands, indicative of N- and C-terminal proteolytic cleavage. These findings are of importance for the development of future cTnT assays, calibrators and quality control samples.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Homo Sapiens (ncbitaxon:9606)

SUBMITTER: Will KWH Wodzig

PROVIDER: MSV000080749 | MassIVE | Wed Mar 29 05:47:00 BST 2017

SECONDARY ACCESSION(S): PXD003187

REPOSITORIES: MassIVE

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Publications

Development of a targeted selected ion monitoring assay for the elucidation of protease induced structural changes in cardiac troponin T.

Streng Alexander S AS de Boer Douwe D Bouwman Freek G FG Mariman Edwin C M EC Scholten Arjen A van Dieijen-Visser Marja P MP Wodzig Will K W H WK

Journal of proteomics 20160106

Cardiac troponin T (cTnT) is a highly cardiospecific protein commonly used in the diagnosis of acute myocardial infarction (AMI), but is subject to proteolytic degradation upon its release in the circulation. In this study, a targeted mass spectrometry assay was developed to detect peptides which are differentially present within the different degradation products. cTnT was spiked in human serum and incubated at 37 °C to induce proteolytic degradation. Isolation and fractionation of cTnT and its ...[more]

PMID: 26772903

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