title: Matrix metalloproteinase-9-mediated type III collagen degradation as a novel serological biochemical marker for liver fibrogenesis.
abstract: BACKGROUND
  During fibrogenesis in the liver, in which excessive remodelling of the extracellular matrix (ECM) occurs, both the quantity of type III collagen (CO3) and levels of matrix metalloproteinases (MMPs), including MMP-9, increase significantly. MMPs play major roles in ECM remodelling, via their activity in the proteolytic degradation of extracellular macromolecules such as collagens, resulting in the generation of specific cleavage fragments. These neo-epitopes may be used as markers of fibrosis.
  
  
  OBJECTIVE
  The current study investigated whether a novel enzyme-linked immunosorbent assay (ELISA) assay specifically measuring an MMP-9-cleaved sequence of type III collagen located at position 610 (CO3-610C) may be used as a marker of liver fibrosis.
  
  
  METHODS
  Bile duct ligation (BDL) was performed in 20 rats, with sham operations performed on another 20 rats. Serum levels of the neo-epitope CO3-610C (MMP-mediated type III collagen degradation) were determined with an ELISA at 14 and 28 days post-surgery. Liver fibrosis was evaluated by quantitative digital image analysis of Sirius red-stained formalin-fixed and paraffin-embedded sections. Western blot and densitometry were performed to confirm the CO3-610C ELISA data.
  
  
  RESULTS
  CO3-610C levels in serum increased significantly in BDL rats compared with those undergoing sham operations (% increase: 14 days=153%, P<0.0001; 28 days=134%, P=0.0014). This increase was confirmed by Western blot and densitometry of the identified bands. The CO3-610C levels correlated to liver fibrosis (R(2) =0.23 and P=0.01), as evaluated by quantitative digital histology.
  
  
  CONCLUSIONS
  The data suggest that MMP-9-mediated CO3 turnover is a central event in the pathogenesis of fibrosis, and that the neo-epitope generated may be a novel biochemical marker.
authors.affiliation: Nordic Bioscience, Herlev, Denmark.
authors.forename: Sanne S
authors.initials: SS
authors.lastname: Veidal
authors.forename: Efstathios
authors.initials: E
authors.lastname: Vassiliadis
authors.forename: Natasha
authors.initials: N
authors.lastname: Barascuk
authors.forename: Chen
authors.initials: C
authors.lastname: Zhang
authors.forename: Toni
authors.initials: T
authors.lastname: Segovia-Silvestre
authors.forename: Lloyd
authors.initials: L
authors.lastname: Klickstein
authors.forename: Martin R
authors.initials: MR
authors.lastname: Larsen
authors.forename: Per
authors.initials: P
authors.lastname: Qvist
authors.forename: Claus
authors.initials: C
authors.lastname: Christiansen
authors.forename: Ben
authors.initials: B
authors.lastname: Vainer
authors.forename: Morten A
authors.initials: MA
authors.lastname: Karsdal
mesh_terms: D000818:Animals; D001652:Bile Ducts / Q000601:surgery; D015415:Biomarkers / Q000097:blood; D024061:Collagen Type III / Q000097:blood* / Q000235:genetics; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D000939:Epitopes / Q000097:blood*; D005109:Extracellular Matrix / Q000201:enzymology / Q000473:pathology; D005260:Female; D015870:Gene Expression; D007091:Image Processing, Computer-Assisted; D008026:Ligation / Q000009:adverse effects; D008099:Liver / Q000378:metabolism / Q000473:pathology; D008106:Liver Cirrhosis, Experimental / Q000097:blood* / Q000473:pathology; D020780:Matrix Metalloproteinase 9 / Q000097:blood*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D015415:Biomarkers; D024061:Collagen Type III; D000939:Epitopes; D020780:Matrix Metalloproteinase 9