Here we present a method for in-depth human plasma proteome analysis based on high-resolution isoelectric focusing HiRIEF LC-MS/MS, demonstrating high proteome coverage, reproducibility and the potential for liquid biopsy protein profiling. By integrating genomic sequence information to the MS-based plasma proteome analysis we enable detection of single amino acid variants and for the first time demonstrate transfer of multiple protein variants between mother and fetus across the placenta. We further show that our method has the ability to detect both low abundance tissue-annotated proteins and phosphorylated proteins in plasma, as well as quantitate differences in plasma proteomes between the mother and the newborn as well as changes related to pregnancy.
MS raw data are available via ProteomeXchange with identifier PXD010899.
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Human subjects: The plasma collections were approved by local ethics boards and all participants signed informed consent. The approval identifiers for the corresponding studies are as follows; Healthy normals Dnr 91:164 for men and Dnr 95:298 for women, mother/child 2014/1622-31/2 and female longitudinal 2008/915-31/4.
© 2019, Pernemalm et al.
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