IMMUNOELECTRON MICROSCOPIC OBSERVATIONS ON LEU-7 POSITIVE CELLS IN VIRUS-RELATED CHRONIC LIVER-DISEASES

We investigated the liver biopsies of 78 patients with hepatitis virus -related chronic liver diseases (B type; 14 patients, C type; 64 patie nts) by immuno-electron microscopy with the Leu-7 monoclonal antibody in order to determine the association of NK/K cells in virus-related c hronic liver diseases. Most Leu-7 positive cells in the liver had the Pit cell morphology but a few Pit cells were Leu-7 negative. A few Leu -7 positive cells had neither Pit cell nor typical T cell morphology. No ultrastructural difference was observed in Leu-7 positive cells bet ween hepatitis B virus- and hepatitis C virus-related chronic liver di seases. Regardless of virus type and hepatitis activity, the fine morp hology of extravascular Leu-7 positive cells differed considerably fro m intravascular cells. Leu-7 positive cells were regularly seen in the cellular infiltrates but the ratio of Leu-7 positive cells/whole infi ltrates was low. There was no correlation between the inflammatory act ivity of the disease and the level of Leu-7 positive cell infiltration . A virus aetiology (hepatitis-C or hepatitis-B) did not affect Leu-7 positive cell infiltration. We conclude that NK cells play only a smal l role in the pathogenesis of hepatitis B virus or hepatitis C virus-r elated hepatocytolysis, during the chronic stage.