title: Extracellular matrix proteins in human bile and gallstones.
abstract: OBJECTIVE
  To investigate the presence of extracellular matrix (ECM) proteins in human bile and gallstones and to determine whether they play a role in gallstone formation.
  
  
  METHODS
  ECM components [procollagen-III-peptide (P-III-P), laminin, and hyaluronic acid] in bile from patients with (n = 22) and without (n = 6) gallstone disease were investigated by immunoassay. Bile, gallstones, and serum were assayed for extracellular matrix components in an additional 19 patients with gallstone disease and gallstones were analysed in a third set of 26 patients. The expression of hyaluronic acid synthetase in bile duct and gall bladder epithelia was investigated by immunocytochemistry.
  
  
  RESULTS
  Hyaluronic acid levels were significantly elevated in hepatic and gall bladder bile, but not in the serum of patients with compared with those without gallstone disease (137 versus 81 micrograms/l, respectively; P < 0.05). No differences were found between hepatic and gall bladder bile. Procollagen-III-peptide and laminin were detected in the hepatic bile of patients in both groups. Laminin levels were higher in gall bladder bile than in serum in all patients and measurable amounts of hyaluronic acid were found in gallstones. The amount of hyaluronic acid was inversely correlated to the volume of the gallstone, i.e., the smallest gallstones contained the highest levels of hyaluronic acid. No procollagen-III-peptide or laminin was found in the gallstones. Immunocytochemistry of the epithelial cells of bile duct and gall bladder mucosa stained strongly for hyaluronic acid synthetase.
  
  
  CONCLUSIONS
  Hyaluronic acid as a progenitor of ECM can be detected in bile and is significantly elevated in patients with gallstone disease. Small gallstones contain more hyaluronic acid than large stones, suggesting that hyaluronic acid may play a role in gallstone formation, particularly since it is produced by the epithelial lining of bile ducts and is found in gall bladder mucosa.
authors.affiliation: Department of Medicine, University of Rostock, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Löhr
authors.forename: R
authors.initials: R
authors.lastname: Scherer
authors.forename: H T
authors.initials: HT
authors.lastname: Schneider
authors.forename: A
authors.initials: A
authors.lastname: May
authors.forename: E G
authors.initials: EG
authors.lastname: Hahn
authors.forename: H
authors.initials: H
authors.lastname: Zirngibl
authors.forename: G
authors.initials: G
authors.lastname: Klöppel
authors.forename: C
authors.initials: C
authors.lastname: Ell
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001646:Bile / Q000737:chemistry*; D001652:Bile Ducts / Q000737:chemistry; D002769:Cholelithiasis / Q000737:chemistry*; D016326:Extracellular Matrix Proteins / Q000032:analysis*; D005260:Female; D005704:Gallbladder / Q000737:chemistry; D014453:Glucuronosyltransferase / Q000032:analysis; D016695:Glycosyltransferases; D006801:Humans; D000076002:Hyaluronan Synthases; D006820:Hyaluronic Acid / Q000032:analysis; D007150:Immunohistochemistry; D007797:Laminin / Q000032:analysis; D008297:Male; D008565:Membrane Proteins; D008875:Middle Aged; D009092:Mucous Membrane / Q000737:chemistry; D010446:Peptide Fragments / Q000032:analysis; D011347:Procollagen / Q000032:analysis; D014166:Transferases; D029867:Xenopus Proteins
chemical_list: D016326:Extracellular Matrix Proteins; D007797:Laminin; D008565:Membrane Proteins; D010446:Peptide Fragments; D011347:Procollagen; D029867:Xenopus Proteins; C041876:procollagen Type III-N-terminal peptide; D006820:Hyaluronic Acid; D014166:Transferases; D016695:Glycosyltransferases; D014453:Glucuronosyltransferase; C056944:HAS1 protein, Xenopus; D000076002:Hyaluronan Synthases