Hepatitis B core antigen expression pattern reflects the response to anti-viral treatment

In hepatitis B early antigen (HBeAg)-negative patients, response predictors to current treatment regimens are not well known. Hepatocyte cell cycle may influence hepatitis B virus (HBV) replication and hepatitis B core antigen (HBcAg) expression, which is a major target for antiviral immune response. The aim of the present paper was to evaluate the role of HBcAg expression in liver tissue and the rate of hepatocyte proliferation in response to antiviral treatment in chronic hepatitis B.

A total of 33 chronic hepatitis B patients (nine HBeAg positive, 24 HBeAg negative) treated with either lamivudine and interferon combined or lamivudine alone were included. Liver expressions of proliferating cell nuclear antigen (PCNA) and HBcAg were immunohistochemically determined. The HBV-DNA levels were measured by a hybrid capture assay. Complete response was defined as alanine aminotransferase (ALT) normalization and HBV-DNA negativity.

At the end of treatment, 23 patients (67.7%) were responders (12 of 23 were sustained responders), while 10 (33.3%) were non-responders. Age, sex, ALT, HBV-DNA levels, HBeAg status, histological activity, fibrosis scores and PCNA labeling index were similar in responders versus non-responders at baseline. The number of patients with positive HBcAg staining was lower in responders compared to non-responders at the end of treatment (17.4% vs 80%, respectively, P < 0.001), although a similar number of sustained responders and non-responders had positive HBcAg staining.

Absence or a low level of HBcAg expression may predict the end of treatment response to current therapies, especially in HBeAg (-) patients. The PCNA determination does not predict treatment response.