title: Absolute and multiplex quantification of antibodies in serum using PSAQ™ standards and LC-MS/MS.
abstract: BACKGROUND
  In preclinical studies, monoclonal antibodies (mAbs) are traditionally assayed by ligand-binding-assays. Recently, quantitative liquid chromatography mass spectrometry (MS)-based assays have emerged which circumvent a number of challenges. These assays may also be multiplex, making them potentially compatible with pharmacokinetic assays for combined antibody therapies.
  
  
  METHODS
  We combined a quantitative MS-based approach with the protein standard for absolute quantification (PSAQ™) strategy to simultaneously quantify three mAb variants presenting minor sequence differences. Stable isotopically labeled mAbs were produced and used as quantification standards. Titration curves were performed to assess the analytical performances of the method. LC-MS/MS and ELISA data were cross-compared.
  
  
  RESULTS
  The approach presented provides similar accuracy and precision than ELISA, while being multiplex and faster to develop. It has applications at all stages of the pharmaceutical development.
authors.affiliation: 1PROMISE Advanced Proteomics, Grenoble, F-38040, France.
authors.forename: Dorothee
authors.initials: D
authors.lastname: Lebert
authors.affiliation: 1PROMISE Advanced Proteomics, Grenoble, F-38040, France.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Picard
authors.affiliation: 2Centre d'Immunologie Pierre Fabre (CIPF), 5 Av. Napoléon III, BP 60497, 74164 Saint-Julien-en-Genevois, France.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Beau-Larvor
authors.affiliation: 2Centre d'Immunologie Pierre Fabre (CIPF), 5 Av. Napoléon III, BP 60497, 74164 Saint-Julien-en-Genevois, France.
authors.forename: Lysiane
authors.initials: L
authors.lastname: Troncy
authors.affiliation: 2Centre d'Immunologie Pierre Fabre (CIPF), 5 Av. Napoléon III, BP 60497, 74164 Saint-Julien-en-Genevois, France.
authors.forename: Christine
authors.initials: C
authors.lastname: Lacheny
authors.affiliation: 3Centre d'Etudes Pré-Cliniques Pierre Fabre, Campans, France.
authors.forename: Bernadette
authors.initials: B
authors.lastname: Maynadier
authors.affiliation: 4PX-Therapeutics, Grenoble, F-38040, France.
authors.forename: Walter
authors.initials: W
authors.lastname: Low
authors.affiliation: 1PROMISE Advanced Proteomics, Grenoble, F-38040, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Mouz
authors.affiliation: 5Université Grenoble Alpes, iRTSV-BGE, F-38000 Grenoble, France.|6CEA, iRTSV-BGE, F-38000 Grenoble, France.|7INSERM, BGE, F-38000 Grenoble, France.
authors.forename: Virginie
authors.initials: V
authors.lastname: Brun
authors.affiliation: 2Centre d'Immunologie Pierre Fabre (CIPF), 5 Av. Napoléon III, BP 60497, 74164 Saint-Julien-en-Genevois, France.
authors.forename: Christine
authors.initials: C
authors.lastname: Klinguer-Hamour
authors.affiliation: 5Université Grenoble Alpes, iRTSV-BGE, F-38000 Grenoble, France.|6CEA, iRTSV-BGE, F-38000 Grenoble, France.|7INSERM, BGE, F-38000 Grenoble, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Jaquinod
authors.affiliation: 2Centre d'Immunologie Pierre Fabre (CIPF), 5 Av. Napoléon III, BP 60497, 74164 Saint-Julien-en-Genevois, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Beck
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000097:blood* / Q000737:chemistry; D002853:Chromatography, Liquid / Q000379:methods*; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood* / Q000737:chemistry; D008969:Molecular Sequence Data; D051381:Rats; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D000911:Antibodies, Monoclonal; D007074:Immunoglobulin G