CHARACTERIZATION AND RESPONSE TO INTERLEUKIN-1 AND TUMOR-NECROSIS-FACTOR OF IMMORTALIZED MURINE BILIARY EPITHELIAL-CELLS

Background & Aims: Biliary epithelial cells are the target of numerous immune-mediated liver diseases, yet their role in pathogenesis remain s unclear because of difficulties in obtaining pure preparations. The aim of this study was to establish pure clones of immortalized murine intrahepatic biliary epithelial cells. Methods: The transgenic mouse h arboring the SV40 thermosensitive immortalizing mutant gene TsA58 unde r the control of the major histocompatibility complex class I promoter was used to establish conditionally immortalized intrahepatic bile du ct cells by countercurrent centrifugal elutriation and clonal dilution . Results: Immortalized clones of cells expressing cytokeratin 19, whi ch organized themselves into ductlike structures, were obtained. On el ectron-microscopic sections, cells were well differentiated and polari zed. Cells proliferate in response to epidermal growth factor, interle ukin la, and tumor necrosis factor a. Using the reverse-transcriptase polymerase chain reaction technique, these cells were found to contain messenger RNA, which encodes for the interleukin 1 and tumor necrosis factor receptors. Conclusions: The availability of unlimited numbers of pure bile duct cells that behave in an identical fashion to biliary epithelial cells from ''normal'' mice will allow for more rigorous st udies of the behavior and function of this epithelium.