CHANGES IN HBV-SPECIFIC DNA POLYMERASE ACTIVITY IN RELATION TO THE SEVERITY OF HBsAg POSITIVE CHRONIC LIVER DISEASE

The method for assay of HBV-specific DNA polymerase (DNA-P) activity was studied and the DNA-P activity in HBsAg positive hemodialysis patients, asymptomatic HBsAg carriers and patients with HBsAg positive chronic liver disease were measured to investigate the relation between HBV replication and occurrence of liver injuries. The normal level (negative) of the DNA-P activity as measured by our method was 18±5cpm. The level below 30cpm was defined as negative. In 81 (89%) of 91 HBeAg positive patients (MO or RIA method), the DNA-P activity was positive, but there was no significant correlation (r=0.329) between the DNA-P activity and HBe ratio in RIA. The severity of liver diseases were inversely correlated with the levels of DNA-P activity. The DNA-P activity rose early to the maximum level, preceding the elevation of transaminase activity. This indicates the time lag between the HBV replication and the onset of liver injuries. The above results confirmed the absence of a direct relationship between the viral replication in the liver or release of HBV from liver cell and liver damege in chronic HBV carriers, suggesting the importance of host immune response to HBV released to the liver cell membrane and the changes of the liver cell membrane related to HBV.