title: A novel LC-MS/MS assay for heparan sulfate screening in the cerebrospinal fluid of mucopolysaccharidosis IIIA patients.
abstract: OBJECTIVE
  Heparan sulfate (HS) accumulates in the central nervous system in mucopolysaccharidosis III type A (MPS IIIA). A validated LC-MS/MS assay was developed to measure HS in human cerebrospinal fluid (CSF).
  
  
  RESULTS
  HS was extracted and digested and the resultant disaccharides were derivatized with a novel label, 4-butylaniline, enabling isoform separation and isotope-tagged analog introduction as an internal standard for LC-MS/MS. The assay has a LLOQ for disaccharides of 0.1 μM, ±20% accuracy and ≤20% precision. CSF samples from patients with MPS IIIA showed elevated HS levels (mean 4.9 μM) compared with negative controls (0.37 μM).
  
  
  CONCLUSIONS
  This assay detected elevated HS levels in the CSF of patients with MPS IIIA and provides a method to assess experimental therapies.
authors: Shire, 300 Shire Way, Lexington, MA 02421, USA.
authors: Hicham
authors: H
authors: Naimy
authors: Tandem Labs - RTP, A LabCorp Company, 2202 Ellis Road, Suite D, Durham, NC 27703, USA.
authors: Kendall D
authors: KD
authors: Powell
authors: Tandem Labs - RTP, A LabCorp Company, 2202 Ellis Road, Suite D, Durham, NC 27703, USA.
authors: John R
authors: JR
authors: Moriarity
authors: Shire, 300 Shire Way, Lexington, MA 02421, USA.
authors: Jiang
authors: J
authors: Wu
authors: Shire, 300 Shire Way, Lexington, MA 02421, USA.
authors: Thomas G
authors: TG
authors: McCauley
authors: Shire, 300 Shire Way, Lexington, MA 02421, USA.|Current address: Agios Pharmaceuticals, 88 Sidney Street, Cambridge, MA 02139, USA.
authors: Patrick Aj
authors: PA
authors: Haslett
authors: Shire, 300 Shire Way, Lexington, MA 02421, USA.|Current address: Alnylam Pharmaceuticals, Inc, 300 Third Street, Cambridge, MA 02142, USA.
authors: Ann J
authors: AJ
authors: Barbier
authors: Shire, 300 Shire Way, Lexington, MA 02421, USA.
authors: Yongchang
authors: Y
authors: Qiu
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D002853:Chromatography, Liquid / Q000379:methods* / Q000592:standards; D006497:Heparan Sulfate / Q000134:cerebrospinal fluid* / Q000302:isolation & purification; D006801:Humans; D007223:Infant; D057230:Limit of Detection; D009084:Mucopolysaccharidosis III / Q000134:cerebrospinal fluid*; D012016:Reference Values; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D006497:Heparan Sulfate
keywords: fit-for-purpose validation; reductive amination; reversed-phase chromatography; stable-isotope labeling; surrogate disaccharides