In vitro duct-like structure formation after isolation of bile ductular cells from a murine model.

The epithelium of the biliary tree is involved in the response to numerous liver disease processes including immunologic destruction during liver transplant rejection and liver graft-versus-host disease after bone marrow transplantation. Furthermore, very little is known concerning the function of this previously inaccessible epithelium, because attempts to isolate and culture biliary cells have been unsuccessful until recently. We present a method for the isolation and culture of bile ductular cells from mice with external bile duct obstruction. Over 85% of the isolated cells stain positive for cytokeratin 19, which is characteristic of murine biliary epithelium. Incubation with recombinant murine gamma-interferon resulted in increased class II antigen expression on the isolated cell surface. When these cells were placed, on a basement membrane matrix, they formed duct-like structures composed of cells that had the morphologic characteristics of bile ductular epithelium when examined by transmission electron microscopy. The ability to isolate murine biliary epithelium that forms duct-like structures will be useful for the in vitro study of biliary epithelial characteristics and injury.