Antibody dependent cellular cytotoxicity in chronic active liver diseases.

Antibody-dependent cellular cytotoxicity (ADCC) of peripheral blood lymphocytes for Chang cells coated with antibody to liver specific membrane lipoprotein was studied in patients with chronic active liver diseases (CALD) to investigate the pathogenesis of liver cell injury. Of 20 CALD patients, a reduced ADCC was found in 5 cases, whereas an increased ADCC was noted in 8 cases. The remaining 7 cases showed a normal ADCC. There was a significant correlation (p less than 0.01) between a decreased ADCC and an increased level of immune complexes in the sera of CALD patients when a 125I-Clq binding test was used. When sera from ADCC patients, which had a high level of circulating immune complexes, or aggregated human IgG was added, ADCC of normal lymphocytes was significantly inhibited (p less than 0.01) compared with that of lymphocytes alone. These results suggest that circulating immune complexes play a role on the pathogenesis of liver damage in CALD.