Antibody to hepatitis B core antigen (anti-HBc) was measured by radioimmunoassay using CORAB (Abbott Laboratories) in 10 cases of chronic persistent hepatitis (CPH), 46 cases of chronic aggressive hepatitis (CAH), 33 cases of liver cirrhosis (LC) and 53 cases of hepatocellular carcinoma (HCC) in relation to hepatitis B surface antigen (HBsAg) and its antibody (anti-HBs). Ninety-eight point four percent of patients with HBsAg and 93.8% of patients with anti-HBs were positive for anti-HBc and the titers of anti-HBc in patients with HBsAg were significantly higher than those with anti-HBs. Thirty-five point five percent of patients negative for either HBsAg or anti-HBs were positive for anti-HBc. The titers of anti-HBc in patients with CPH, CAH and LC were relatively low, whereas 7 (46.8%) of the HCC patients negative for either HBsAg or anti-HBc had high titers of anti-HBc. The significance of the presence of anti-HBc alone is discussed.</p
