title: Mass spectrometry-based plasma peptide profiling of acute exacerbation in HBeAg-positive chronic hepatitis B.
abstract: BACKGROUND
  Acute exacerbations (AE) of serum alanine aminotransferase activities that are 5 times above the normal upper limit frequently occur during the immune clearance phase of hepatitis Be antigen (HBeAg)-positive chronic hepatitis B (CHB). It is unclear how the varying clinical severities of AE reflect differences in the underlying immune responses against the hepatitis B virus.
  
  
  METHODS
  We utilized magnetic bead-based purification methods coupled with MALDI-TOF mass spectrometry to generate plasma peptide profiles from HBeAg-positive CHB patients experiencing AE without and with clinical decompensation.
  
  
  RESULTS
  Hydrophobic interaction chromatography (HIC C18) provided a more discriminatory spectral profile than immobilized Cu(2+) metal ion affinity chromatography did for diagnosis of a clinical spectrum of AEs. Using the sorting algorithm, Support Vector Machine, a classification model consisting of 5 classifiers was determined to give a sensitivity of 94.7% and a specificity of 75% for differentiating patients with and without decompensation. Classifiers identified as fragments derived from transthyretin and apolipoprotein A-IV were significantly decreased and increased in patients with decompensation, respectively.
  
  
  CONCLUSIONS
  Our study demonstrated that HIC C18 fractionation coupled with MALDI-TOF mass spectrometry can be used for differentiating AE with and without decompensation in patients with HBeAg-positive CHB.
authors.affiliation: Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, Taiwan.
authors.forename: Eric C
authors.initials: EC
authors.lastname: Han
authors.forename: Ying-Shiung
authors.initials: YS
authors.lastname: Lee
authors.forename: Yu-Ching
authors.initials: YC
authors.lastname: Liu
authors.forename: Hsin-Yi
authors.initials: HY
authors.lastname: Liao
authors.forename: Wen-Sin
authors.initials: WS
authors.lastname: Liao
authors.forename: Hsueh-Chou
authors.initials: HC
authors.lastname: Lai
authors.forename: Cheng-Yuan
authors.initials: CY
authors.lastname: Peng
authors.forename: Long-Bin
authors.initials: LB
authors.lastname: Jeng
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods*; D006513:Hepatitis B e Antigens / Q000097:blood*; D019694:Hepatitis B, Chronic / Q000097:blood*; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods*
chemical_list: D006513:Hepatitis B e Antigens