Studies on pre-S2 antigen and antibody in various HBV infection

Pre-S2 antigen and anti-pre-S2 antibody were tested in 56 sera of 6 patients with acute hepatitis type B and 867 sera of 265 cases with chronic HBV infection. Pre-S2 antigen could be detected in almost all sera HBsAg titer more than 24 by RPHA. On the other hand, anti-pre-S2 antibody could be detected in 4 of 6 patients with acute hepatitis type B 2 or 3 weeks before the clearance of serum HBsAg. Anti-pre-S2 antibody could be detected in 85 of 238 cases with chronic HBV infection, and the titer of HBsAg and DNA-polymerase activity in anti-pre-S2 positive patients were statistically lower than those in anti-pre-S2 negative patients. Serially long-term follow-up study in 15 of 27 chronic hepatitis patients demonstrated that detection of anti-pre-S2 antibody was divided into three patterns; persistent positive, fluctuating and one-point positive. Although only 2 out of 7 patients with persisting high level HBe antigen were positive for anti-pre-S2, it could be detected in 7 out of 10 cases recognized spontaneous disappearance of HBeAg. Detection pattern in 5 of those 7 patients showed one-point pattern just before the clearance of serum HBeAg. These results may suggest the correlation between appearance of anti-pre-S2 and the clearance of HBeAg.