Induction of liver fibrosis by EpCAM positive immature biliary epithelial cells in biliary atresia

Abstract

Objective To explore the relationship between EpCAM positive immature biliary epithelial cells (BECs) and liver fibrosis in biliary atresia (BA) patients and elucidate the role of immature BECs in BA. Methods Liver samples were collected from January 2012 to June 2015, including BA (n=65), choledochal cyst (CC, n=25) and cavernous transformation of portal vein (CTPV, n=15). Immunohistochemical staining of CK19, EpCAM and saturated picric acid sirius red staining were performed for BEC maturation and liver fibrosis. Imaging and statistical software were used for positive cell counting and statistical analyses. Results In CTPV group, the morpohology of bile ducts was basically normal and CK19 positivity indicated mature BECs. No hyperplasia was found in BECs. And proliferative BECs were found in BA and CC with liver fibrosis. The BECs adjacent to liver fibrosis area were predominantly EpCAM positive immature BECs. Furthermore, statistically significant correlation was observed between EpCAM positive immature BECs and degree of liver fibrosis in BA (r=0.56, P<0.001). Conclusions The proliferation of EpCAM positive immature BECs may be primarily responsible for rapidly progressive fibrosis in BA. Key words: Bliary atresia; Liver cirrhosis; Immunohistochemistry