Three-dimensional reconstructions of intrahepatic bile duct tubulogenesis in human liver

Abstract

BackgroundDuring liver development, intrahepatic bile ducts are thought to arise by a unique asymmetric mode of cholangiocyte tubulogenesis characterized by a series of remodeling stages. Moreover, in liver diseases, cells lining the Canals of Hering can proliferate and generate new hepatic tissue. The aim of this study was to develop protocols for three-dimensional visualization of protein expression, hepatic portal structures and human hepatic cholangiocyte tubulogenesis.ResultsProtocols were developed to digitally visualize portal vessel branching and protein expression of hepatic cell lineage and extracellular matrix deposition markers in three dimensions. Samples from human prenatal livers ranging from 7 weeks + 2 days to 15½ weeks post conception as well as adult normal and acetaminophen intoxicated liver were used. The markers included cytokeratins (CK) 7 and 19, the epithelial cell adhesion molecule (EpCAM), hepatocyte paraffin 1 (HepPar1), sex determining region Y (SRY)-box 9 (SOX9), laminin, nestin, and aquaporin 1 (AQP1).Digital three-dimensional reconstructions using CK19 as a single marker protein disclosed a fine network of CK19 positive cells in the biliary tree in normal liver and in the extensive ductular reactions originating from intrahepatic bile ducts and branching into the parenchyma of the acetaminophen intoxicated liver. In the developing human liver, three-dimensional reconstructions using multiple marker proteins confirmed that the human intrahepatic biliary tree forms through several developmental stages involving an initial transition of primitive hepatocytes into cholangiocytes shaping the ductal plate followed by a process of maturation and remodeling where the intrahepatic biliary tree develops through an asymmetrical form of cholangiocyte tubulogenesis.ConclusionsThe developed protocols provide a novel and sophisticated three-dimensional visualization of vessels and protein expression in human liver during development and disease.

Expression of Tight Junction Components in Hepatocyte-Like Cells Differentiated from Human Embryonic Stem Cells

“…Clostridium perfringens enterotoxin binds specifically to hepatocytes, and causes pyogenic liver abscess [68]. Claudin-4 can be found in cholangiocyte tumors and cholangiocytes too [7,29], and cytokeratin-7 is a conventional markers of cholangiocytes [11,12]. In our experiments the gene expression of claudin-4 significantly increased and reached the highest level in the cells at the end of the differentiation.…”

“…Consequently, the biliary type cytokeratins, CK-7, CK-8, CK-18, and CK-19 are highly expressed in cholangiocarcinomas [12,13]. 4 Hepatic ABC transporters greatly contribute to various functions of liver cells.…”

Left Hemiliver Medial Sector-Portal Venous Anatomy

“…The human liver regeneration follows after hepatic resection [9,10] and during development and disease. [11] This capacity of the liver to regenerate contributed to introduction of preoperative procedures that stimulate liver hypertrophy. During right hepatectomy Farges et al assessed the impact of liver hypertrophy of the FLR induced by preoperative Portal Vein Embolization-PVE.…”

Hepatocellular carcinoma may display elevated nestin expression in endothelial cells: experimental study

“…4 Moreover, hepatic stem cells, which express nestin, have been characterized in cultured adult human liver cells in vitro. 5 However, controversy continues regarding the phenotypic and histological features of human hepatic stem cells.…”