Change of Intrahepatic Expression of Hepatitis-B Core Antigen during the Clinical Course of Type-B Chronic Hepatitis

Abstract

The intrahepatic expression of hepatitis-B core antigen (HBcAg) was investigated in 54 liver biopsy specimens from 24 chronic type-B hepatitis patients, by the peroxidase-anti-peroxidase technique. The HBcAg localization pattern in the hepatocyte correlated with the evolution of serum alanine aminotransferase (ALAT) values. The clinical course were classified into three phases, as follows: pre-exacerbation phase (A phase), with minimal abnormal range of ALAT (40–100 KU) for 6 to 12 months; exacerbation phase (B phase) with elevated ALAT (more than 100 KU) for 3 to 6 months; and post-exacerbation and subsiding phase (C phase) for 3 months after phase B, showing decreased ALAT values. Nineteen of the 54 biopsied specimens belonged to the A phase, 21 to the B phase, and 14 to the C phase. In the A phase the hepatocytic HBcAg was variably expressed as nuclear, cytoplasmic, and membranous in location in the same specimens. In the B phase, HBcAg expression decreased in the nucleus, but increased in the cytoplasmic-membranous pattern. The intrahepatic HBcAg expression in the C phase decreased in all patterns. The mean level of ALAT in cases of cytoplasmic-membranous HBcAg expression was higher than that in cases of nuclear HBcAg expression. Four of six patients who underwent liver biopsies in the A, B, and C phases showed remarkable decreases of cytoplasmic and membranous HBcAg expression in the C phase. These findings suggest that cytoplasmic and membranous localization of HBcAg can be related to both liver cell injury and active inflammatory processes. However, as there were patients with cytoplasmic-membranous HBcAg expression and low ALAT level and others with nuclear HBcAg expression and high ALAT level, the other co-factors should be considered as the cause of liver damage.

Key Words:

• HBcAg in liver
• peroxidase-anti-peroxidase method
• type-B chronic hepatitis