title: Immunohistochemical study of the phenotypic change of the mesenchymal cells during portal tract maturation in normal and fibrous (ductal plate malformation) fetal liver.
abstract: BACKGROUND
  In adult liver, the mesenchymal cells, portal fibroblasts and vascular smooth muscle cells can transdifferentiate into myofibroblasts, and are involved in portal fibrosis. Differential expression of markers, such as alpha-smooth muscle actin (ASMA), h-caldesmon and cellular retinol-binding protein-1 allows their phenotypic discrimination. The aim of our study was to explore the phenotypic evolution of the mesenchymal cells during fetal development in normal liver and in liver with portal fibrosis secondary to ductal plate malformation in a series of Meckel-Gruber syndrome, autosomal recessive polycystic kidney disease and Ivemark's syndrome.
  
  
  RESULTS
  At the early steps of the portal tract maturation, portal mesenchymal cells expressed only ASMA. During the maturation process, these cells were found condensed around the biliary and vascular structures. At the end of maturation process, only cells around vessels expressed ASMA and cells of the artery tunica media also expressed h-caldesmon. In contrast, ASMA positive cells persisted around the abnormal biliary ducts in fibrous livers.
  
  
  CONCLUSIONS
  As in adult liver, there is a phenotypic heterogeneity of the mesenchymal cells during fetal liver development. During portal tract maturation, myofibroblastic cells disappear in normal development but persist in fibrosis following ductal plate malformation.
authors: INSERM U889, Université Bordeaux2, F-33076 Bordeaux, France. julienvilleneuve27@hotmail.com
authors: Julien
authors: J
authors: Villeneuve
authors: Fanny
authors: F
authors: Pelluard-Nehme
authors: Chantal
authors: C
authors: Combe
authors: Dominique
authors: D
authors: Carles
authors: Christine
authors: C
authors: Chaponnier
authors: Jean
authors: J
authors: Ripoche
authors: Charles
authors: C
authors: Balabaud
authors: Paulette
authors: P
authors: Bioulac-Sage
authors: Sébastien
authors: S
authors: Lepreux