| Theme |
Current Topics in Hepatitis viruses |
| Title |
Hepatitis B Surface Antigen Negative Chronic Hepatitis Type B |
| Author |
Tohru Shizuma |
Division of Medicine. Institute of Gastroenterology, Tokyo Women's |
| Author |
Kiyoshi Hasegawa |
Division of Medicine. Institute of Gastroenterology, Tokyo Women's |
| [ Summary ] |
The recent development of molecular biology techniques has made possible the detection of hepatitis B virus (HBV) in some chronic hepatitis B patients whose hepatitis B surface antigen (HBsAg) has been cleared. Although the precise mechanism of this paradoxical phenomenon has not been elucidated, three possibilities can be considered ; 1) an increased immune response may eliminate HBsAg, 2) altered antigenecity of HBsAg, 3) suppression of HBV-DNA replication. Among these, recent data support the possibility of genetic alterations in pre-S/S regions, the p-region and the X-region that result in the suppression of HBV-DNA replication. In this article, we discuss these possibilities based on the recent findings of molecular analysis of HBV-DNA. |