Fliv-1: A surface membrane differentiation antigen of fetal rat hepatocytes

A monoclonal antibody of IgGl subclass was raised against 15 day fetal hepatocytes. The antibody appears to recognize a surface membraneassociated fetal hepatocyte antigen. Preliminary experiments suggest that the antibody recognizes a protein epitope. The tissue distribution of the antigen, designated Fliv-1, was studied by immunoperoxidase staining on whole body sections from fetal rats of different gestational ages. In 15 day fetal rats the antigen was detected on Rathke's pouch, brain infundibulum, tongue, liver, pancreatic acini, adrenal gland, vertebral myotome, and some developing muscle tissue. All normal adult tissues that were examined, two rat hepatoma cell lines, and hepatomas induced in rats by a single injection of diethylnitrosamine, were negative for the Fliv-1 antigen. On the basis of its tissue distribution, it seems unlikely that Fliv-1 is a previously described fetal hepatocyte marker.