title: Preservation of bile ductules mitigates bile duct loss.
abstract: The finer branches of the biliary tree (FBBT) contain a regenerative compartment. We hypothesized that preservation of the FBBT together with its microvasculature will lead to recovery of biliary damage and prolonged preservation of bile ductules during the development of chronic liver allograft rejection. The interlobular bile ducts, portal bile ductules and extraportal biliary cells with and without microvessels were studied in sequential biopsies in five patients who fulfilled the Banff criteria of early chronic rejection (CR) (imminence group). Biopsies of CR patients (n = 12) served as controls. Biopsies were double immunostained with CD34 (microvessels) and cytokeratin 7 (biliary structures). Proliferation and proangiogenic activity were assessed with Ki67 and VEGF-A immunostaining. Severe damage of bile ducts in the imminence group did not progress to significant bile duct loss. This was associated with a high proliferative activity in all biliary structures and preservation of the microvascular compartment. VEGF-A expression was increased in all but the reperfusion biopsies. In conclusion, both regenerative activity of the FBBT and an intact microvascular compartment are associated with less damage of the biliary tree and could therefore be prerequisites for biliary regeneration.
authors.affiliation: Department of Pathology and Laboratory Medicine, University Medical Center Groningen, the Netherlands. m.c.van.den.heuvel@path.umcg.nl
authors.forename: M C
authors.initials: MC
authors.lastname: van den Heuvel
authors.forename: K P
authors.initials: KP
authors.lastname: de Jong
authors.forename: M
authors.initials: M
authors.lastname: Boot
authors.forename: M J H
authors.initials: MJ
authors.lastname: Slooff
authors.forename: S
authors.initials: S
authors.lastname: Poppema
authors.forename: A S H
authors.initials: AS
authors.lastname: Gouw
mesh_terms: D000293:Adolescent; D000328:Adult; D017734:Bile Ducts, Extrahepatic / Q000473:pathology* / Q000503:physiopathology; D001653:Bile Ducts, Intrahepatic / Q000473:pathology* / Q000503:physiopathology; D002455:Cell Division; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007231:Infant, Newborn; D008111:Liver Function Tests; D016031:Liver Transplantation / Q000473:pathology* / Q000502:physiology; D009926:Organ Preservation; D012038:Regeneration