Monoclonal antibodies to rat liver cell membrane glycoproteins

Monoclonal antibodies were raised against membrane glycoproteins prepared from rat liver using lentil-lectin affinity chromatography. Monoclonal antibodies to rat hepatocytes with three different characteristics were obtained and designated as HAM.1, HAM.2 and HAM.3. The binding characteristics of these three monoclonal antibodies were analysed by flow cytofluorography and indirect radioimmunoassay; HAM.3 recognized a membrane antigen restricted mainly to hepatocytes. However, most rat hepatoma cell lines tested failed to express this antigen. Thus, this antibody might be useful for analysing the molecular nature of a liver-specific antigen or the membrane molecules on the normal and malignantly transformed hepatocytes. All the rat hepatoma cell lines tested were labeled with HAM.1 which recognized a membrane antigen on both hepatocytes and lymphocytes, although the amount of antigen expression was quite low on lymphocytes. HAM.2 was found to recognise the Class 1 (RT-1A) histocompatibility antigen. This antigen was purified from rat liver with a HAM.2-affinity column.