CLINICAL-STUDY OF IGA ANTIBODY AGAINST HEPATITIS-C VIRUS CORE - ANTIGEN IN PATIENTS WITH TYPE-C CHROMIC LIVER-DISEASE

Immunoglobulin A class antibody to hepatitis C virus core antigen (IgA anti-HCc) was measured in the serum of 128 patients with type C chron ic liver disease. Fifty-eight patients (45.3%) were seropositive. IgA anti-HCc was detected in only one of 20 patients with chronic persiste nt hepatitis; however, 52.3% (46/88) of patients with chronic active h epatitis and 55% (11/20) of patients with liver cirrhosis were seropos itive. Histological examination revealed that 22 (71.0%) of 31 patient s with severe disease activity were seropositive compared to 35 (44.9% ) of 78 patients with moderate (P < 0.05) and one (5.3%) of 19 patient s with mild (P < 0.01) histological changes. IgA anti-HCc was measured sequentially in 65 patients who underwent interferon therapy. There w as a significant difference between responders and other patients in t he mean ratio of IgA anti-HCc titers one month after therapy. Three mo nths after therapy, IgA anti-HCc was detectable in only two of 15 resp onders who were IgA anti-HCc seropositive at the start of therapy. In contrast, IgA anti-HCc reappeared three months after therapy despite a temporary decrease to undetectable levels in all nonresponders. We co nclude that IgA anti-HCc is a useful marker to identify the presence o f active type C liver disease and that the disappearance of IgA anti-H Cc three months after interferon therapy predicts a good response in t reated patients.