title: Quantification of αS1-casein in breast milk using a targeted mass spectrometry-based approach.
abstract: The caseins comprise a milk protein fraction of high nutritional value and, as more recently discovered, of immunologic relevance. In particular, αS1-casein (CSN1S1) is of interest being a potential autoantigen. So far, the concentration of caseins in human milk was primarily determined by indirect methods. The aim of this study was to directly measure the CSN1S1 content in breast milk using mass spectrometry (MS). The quantification was based on tryptic CSN1S1 peptides with the best response in liquid chromatography (LC)-MS/MS analysis. Targeted experiments allowed both specific and sensitive detection at the low fmol level. For this pilot study, twenty breast milk samples of the first week post-partum were analyzed and contained between 3 and 540μg/ml CSN1S1. Limitations of CSN1S1 quantification are discussed.
authors.affiliation: Heinrich-Heine-Universität Düsseldorf, Department of Rheumatology, Moorenstr. 5, 40225 Düsseldorf, Germany; Westfälische Wilhelms-Universität Münster, PharmaCampus, Institute of Pharmaceutical and Medicinal Chemistry, Corrensstr. 48, 48149 Münster, Germany. Electronic address: irinaa@gmx.net.
authors.forename: Irina
authors.initials: I
authors.lastname: Altendorfer
authors.affiliation: Westfälische Wilhelms-Universität Münster, Core Unit Proteomics, Interdisciplinary Center for Clinical Research, Röntgenstr. 21, 48149 Münster, Germany. Electronic address: koenigs@ifg.uni-muenster.de.
authors.forename: Simone
authors.initials: S
authors.lastname: König
authors.affiliation: Westfälische Wilhelms-Universität Münster, PharmaCampus, Institute of Pharmaceutical and Medicinal Chemistry, Corrensstr. 48, 48149 Münster, Germany. Electronic address: a.braukmann@uni-muenster.de.
authors.forename: Achim
authors.initials: A
authors.lastname: Braukmann
authors.affiliation: Westfälische Wilhelms-Universität Münster, PharmaCampus, Institute of Pharmaceutical and Medicinal Chemistry, Corrensstr. 48, 48149 Münster, Germany. Electronic address: thorsten.saenger@uni-muenster.de.
authors.forename: Thorsten
authors.initials: T
authors.lastname: Saenger
authors.affiliation: Heinrich-Heine-Universität Düsseldorf, Department of Rheumatology, Moorenstr. 5, 40225 Düsseldorf, Germany. Electronic address: Bleck@med.uni-duesseldorf.de.
authors.forename: Ellen
authors.initials: E
authors.lastname: Bleck
authors.affiliation: Heinrich-Heine-Universität Düsseldorf, Department of Rheumatology, Moorenstr. 5, 40225 Düsseldorf, Germany. Electronic address: Stefan.Vordenbaeumen@med.uni-duesseldorf.de.
authors.forename: Stefan
authors.initials: S
authors.lastname: Vordenbäumen
authors.affiliation: Heinrich-Heine-Universität Düsseldorf, Department of Gynecology, Moorenstr. 5, 40225 Düsseldorf, Germany. Electronic address: Anna.Kubiak@med.uni-duesseldorf.de.
authors.forename: Anna
authors.initials: A
authors.lastname: Kubiak
authors.affiliation: Heinrich-Heine-Universität Düsseldorf, Department of Rheumatology, Moorenstr. 5, 40225 Düsseldorf, Germany. Electronic address: Matthias.Schneider@med.uni-duesseldorf.de.
authors.forename: Matthias
authors.initials: M
authors.lastname: Schneider
authors.affiliation: Westfälische Wilhelms-Universität Münster, PharmaCampus, Institute of Pharmaceutical and Medicinal Chemistry, Corrensstr. 48, 48149 Münster, Germany. Electronic address: joachim.jose@uni-muenster.de.
authors.forename: Joachim
authors.initials: J
authors.lastname: Jose
mesh_terms: D002364:Caseins / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005260:Female; D006801:Humans; D057230:Limit of Detection; D008895:Milk, Human / Q000737:chemistry*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D002364:Caseins
keywords: Breast milk; Casein; LC–MS/MS; Pseudo-MRM; αS1-casein quantification