[Preparation of monoclonal antibody directed against hepatitis B virus X protein and detection of reactive antigen in hepatocellular carcinoma].

A mouse monoclonal antibody directed against hepatitis B virus (HBV) X protein (HBxAg) was prepared. The antibody was used to screen by immunohistochemistry 50 liver tissue sections from patients with hepatocellular carcinoma (HCC), and 15 patients with chronic active hepatitis (CAH). 28 of 50(56%) samples were HBxAg positive in tumor tissues. The positive rates of HBxAg only in tumor tissues or in adjacent nontumor tissues were 24% and 16%. HBsAg was detected in 16% of cases in tumor tissues and 74% in surrounding nontumor tissues. In CAH samples, the positive rates of HBxAg and HBsAg were 6.6% and 73.3%. HBcAg was only detected in nontumor surrounding liver tissues, the positive rates being 18%. In CAH samples, no HBcAg was detected. The results showed that HBxAg is a common marker in liver tissue from patients with HBV-related HCC. The findings of HBxAg in the absence of detectable HBsAg and HBcAg in the liver tissues suggested that HBxAg could be independent of HBV replication and implied that the synthesis of HBxAg may be directed from integrated HBV DNA templates. It is possible to use antiHBx monoclonal antibody as a carrier for the targeting therapy of HCC.