Hepatic cellular and subcellular expression of hepatitis B virus (HBV) antigens--HBsAg, HBcAg, and HBeAg--in 143 Chinese patients with chronic HBV infection were studied by immunohistochemical techniques. Nuclear expression of HBcAg and nuclear and cytoplasmic expression of HBeAg showed a secular trend decreasing from the carrier state and chronic persistent hepatitis (CPH), through chronic active hepatitis (CAH), to cirrhosis with or without hepatocellular carcinoma. In contrast, cytoplasmic HBcAg expression was significantly greater in patients with CPH and CAH (P < .0108). In addition, cytoplasmic HBcAg correlated significantly with lobular activity, portal inflammation, and hepatitic activity (P < or = .007). Expression of cytoplasmic HBcAg also exceeded cytoplasmic HBeAg and nuclear HBcAg in liver specimens showing significant damage (P < .038). HBsAg, however, showed no secular trend and was not related to liver histology. The authors' findings support the theory that HBcAg is also the viral target antigen for immune-mediated liver damage in Chinese patients with chronic HBV infection.