[Reactivity of 48-1 antibody with human liver tissue]

Reactivity of monoclonal antibody (48-1), produced by the Epstein-Barr Virus (EBV) transformation method using lymphocytes from a chimpanzee infected with non-A, non-B hepatitis, on human liver biopsy specimens from 240 cases was studied. By means of indirect immunoperoxidase study (Secondary Antibody: Horseradish peroxidase labeled anti-human IgM.F(ab')2), the cases with non-A, non-B acute hepatitis showed a high positive reaction (15/24), while those cases with A-type and B-type hepatitis showed almost no reaction, suggesting that this 48-1 antibody strongly related to human non-A, non-B hepatitis. As for staining pattern, cytoplasms of some hepatocytes and large-size histiocytes were stained diffusely in pellet form, and were found scattered in each lobule. In addition, an EM study was made on positive cases using an immunoperoxidase method. However, a definite finding on peroxidase-reactive products was not obtained. We believe that this antibody (48-1) obtained by the EBV method would be useful in investigations of antigen-antibody systems related to non-A, non-B hepatitis.