title: Novel biomarker candidates to predict hepatic fibrosis in hepatitis C identified by serum proteomics.
abstract: BACKGROUND
  Liver biopsy remains the gold standard to assess hepatic fibrosis. It is desirable to predict hepatic fibrosis without the need for invasive liver biopsy. Proteomic techniques allow unbiased assessment of proteins and might be useful to identify proteins related to hepatic fibrosis.
  
  
  OBJECTIVE
  We utilized two different proteomic methods to identify serum proteins as candidate biomarkers to predict hepatic fibrosis stage in patients with chronic hepatitis C virus (HCV) infection.
  
  
  METHODS
  Serum was obtained from 24 people with chronic HCV at time of liver biopsy and from 6 normals. Liver biopsy fibrosis was staged 1-4 (Batts-Ludwig). Pooled serum samples (six in each of four fibrosis groups and controls) were analyzed with 4- and 8-plex isobaric tags for relative and absolute quantitation (iTRAQ), determining protein identification (ID) and ratios of relative protein abundance. Nonpooled samples were analyzed with two-dimensional (2-D) gels and difference in gel electrophoresis (DIGE) comparing different samples on the same gel and across gels. Spots varying among groups were measured with densitometry, excised, digested, and submitted for tandem mass spectrometry (MS/MS) protein ID.
  
  
  RESULTS
  iTRAQ identified 305 proteins (minimum 99% ID confidence); 66 were increased or decreased compared with controls. Some proteins were increased or decreased for specific fibrosis scores. From 704 DIGE protein spots, 66 were chosen, 41 excised, and 135 proteins identified, since one gel spot often identified more than one protein.
  
  
  CONCLUSIONS
  Both proteomic methods identified two proteins as biomarker candidates for predicting hepatic fibrosis: complement C4-A and inter-alpha-trypsin inhibitor heavy chain H4.
authors: Department of Pediatrics, University of Minnesota, 420 Delaware St. SE, MMC 185, Minneapolis, MN 55455, USA. yangx822@umn.edu
authors: Libang
authors: L
authors: Yang
authors: Kyle D
authors: KD
authors: Rudser
authors: LeeAnn
authors: L
authors: Higgins
authors: Hugo R
authors: HR
authors: Rosen
authors: Atif
authors: A
authors: Zaman
authors: Christopher L
authors: CL
authors: Corless
authors: Larry
authors: L
authors: David
authors: Glenn R
authors: GR
authors: Gourley
references: Anal Chem. 1995 Apr 15;67(8):1426-36
references: 7741214
references: Gastroenterology. 2003 Jan;124(1):97-104
references: 12512034
references: Med Sci Monit. 2009 Oct;15(10):RA203-208
references: 19789523
references: Electrophoresis. 2003 Nov;24(21):3800-5
references: 14613208
references: Curr Opin Biotechnol. 2004 Feb;15(1):38-43
references: 15102464
references: Clin Chim Acta. 2009 Nov;409(1-2):90-5
references: 19748500
references: Hepatology. 1994 Jul;20(1 Pt 1):15-20
references: 8020885
references: Hepatology. 2003 Aug;38(2):481-92
references: 12883493
references: Proteomics. 2003 Oct;3(10):1835-62
references: 14625847
references: World J Gastroenterol. 2005 Aug 28;11(32):4997-5001
references: 16124052
references: Lancet. 2008 Mar 8;371(9615):838-51
references: 18328931
references: J Hepatol. 1986;2(2):165-73
references: 3958472
references: Mol Cell Proteomics. 2002 Nov;1(11):845-67
references: 12488461
references: Ann Intern Med. 2000 Feb 15;132(4):296-305
references: 10681285
references: Eur J Gastroenterol Hepatol. 2009 Sep;21(9):990-5
references: 19322100
references: Clin Chem. 2003 Mar;49(3):450-4
references: 12600957
references: Anal Chem. 2004 Feb 15;76(4):1134-44
references: 14961748
references: Nature. 2003 Oct 2;425(6957):441
references: 14523412
references: Obes Surg. 2005 Apr;15(4):497-501
references: 15946428
references: Hepatology. 2009 Oct;50(4):1294-306
references: 19711424
references: Lancet. 1997 Mar 22;349(9055):825-32
references: 9121257
references: Am J Med. 2007 Mar;120(3):280.e9-14
references: 17349453
references: Hepatology. 1996 Aug;24(2):289-93
references: 8690394
references: Brief Funct Genomic Proteomic. 2006 Jun;5(2):112-20
references: 16772272
references: Gut. 2007 Aug;56(8):1098-104
references: 17344277
references: Hepatology. 1996 Jun;23(6):1334-40
references: 8675148
references: Nihon Hoigaku Zasshi. 1984 Dec;38(6):797-803
references: 6543560
references: Nucleic Acids Res. 2003 Jul 1;31(13):3784-8
references: 12824418
references: Hepatology. 2008 Feb;47(2):455-60
references: 18038452
references: Lancet. 2001 Apr 7;357(9262):1069-75
references: 11297957
references: Am J Surg Pathol. 1995 Dec;19(12):1409-17
references: 7503362
references: Electrophoresis. 2006 Apr;27(8):1437-43
references: 16532521
references: Am J Gastroenterol. 1999 Oct;94(10):2977-82
references: 10520855
references: Comp Hepatol. 2002 Dec 30;1(1):3
references: 12537583
references: J Proteome Res. 2002 Jan-Feb;1(1):21-6
references: 12643522
references: Gut. 2003 Mar;52(3):404-9
references: 12584224
references: Hepatology. 2004 Mar;39(3):862-3; author reply 863
references: 14999708
references: Clin Transpl. 1998;:17-37
references: 10503083
references: Gut. 2008 Dec;57(12):1722-7
references: 19022928
references: Gastroenterology. 2002 Dec;123(6):2082-99
references: 12454863
references: Anal Bioanal Chem. 2005 Jun;382(3):669-78
references: 15900442
references: Tunis Med. 2009 May;87(5):307-10
references: 19927759
references: Hepatology. 2008 Aug;48(2):418-31
references: 18563841
references: Mol Cell Proteomics. 2002 Dec;1(12):947-55
references: 12543931
references: Hepatology. 2003 Aug;38(2):518-26
references: 12883497
references: Clin Chem. 2007 Oct;53(10):1792-9
references: 17702858