title: Quantitative analysis of factor P (Properdin) in monkey serum using immunoaffinity capturing in combination with LC-MS/MS.
abstract: OBJECTIVE
  Factor P (Properdin), an endogenous glycoprotein, plays a key role in innate immune defense. Its quantification is important for understanding the pharmacodynamics (PD) of drug candidate(s).
  
  
  RESULTS
  In the present work, an immunoaffinity capturing LC-MS/MS method has been developed and validated for the first time for the quantification of factor P in monkey serum with a dynamic range of 125 to 25,000 ng/ml using the calibration standards and QCs prepared in factor P depleted monkey serum. The intra- and inter-run precision was ≤7.2% (CV) and accuracy within ±16.8% (%Bias) across all QC levels evaluated. Results of other evaluations (e.g., stability) all met the acceptance criteria.
  
  
  CONCLUSIONS
  The validated method was robust and implemented in support of a preclinical PK/PD study.
authors.affiliation: Department of Drug Metabolism & Pharmacokinetics, Novartis Institutes for BioMedical Research, East Hanover, NJ 07936, USA.
authors.forename: Xinliu
authors.initials: X
authors.lastname: Gao
authors.affiliation: Department of Drug Metabolism & Pharmacokinetics, Novartis Institutes for BioMedical Research, East Hanover, NJ 07936, USA.
authors.forename: Hui
authors.initials: H
authors.lastname: Lin
authors.affiliation: Department of Drug Metabolism & Pharmacokinetics, Novartis Institutes for BioMedical Research, Basel, Switzerland.
authors.forename: Carsten
authors.initials: C
authors.lastname: Krantz
authors.affiliation: Department of Drug Metabolism & Pharmacokinetics, Novartis Institutes for BioMedical Research, Basel, Switzerland.
authors.forename: Arlette
authors.initials: A
authors.lastname: Garnier
authors.affiliation: Department of Drug Metabolism & Pharmacokinetics, Novartis Institutes for BioMedical Research, East Hanover, NJ 07936, USA.
authors.forename: Jimmy
authors.initials: J
authors.lastname: Flarakos
authors.affiliation: Department of Drug Metabolism & Pharmacokinetics, Novartis Institutes for BioMedical Research, East Hanover, NJ 07936, USA.
authors.forename: Francis L S
authors.initials: FL
authors.lastname: Tse
authors.affiliation: Department of Drug Metabolism & Pharmacokinetics, Novartis Institutes for BioMedical Research, East Hanover, NJ 07936, USA.
authors.forename: Wenkui
authors.initials: W
authors.lastname: Li
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002846:Chromatography, Affinity / Q000379:methods*; D002853:Chromatography, Liquid / Q000379:methods; D000882:Haplorhini / Q000097:blood*; D057230:Limit of Detection; D011414:Properdin / Q000032:analysis* / Q000493:pharmacokinetics; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D011414:Properdin
keywords: LC–MS/MS; biomarker; factor P (Properdin); immunoaffinity capturing; serum depletion; stable-isotope-labeled peptide internal standard; surrogate peptide