<正> Antiserum against PreS2 peptide was raised with a synthetic polypeptide from the rabbits.The anti-preS2 antibody and polymerized human serum albumin were used as reagents in aradioimmunoassay to detect preS2 and polymerized human serum albumin bindingactivity respectively. Both were absent in patients with hepatitis A or HBsAg negative chronic liver di-seases. In biopsy - proven patients with chronic active hepatitis （CAH）B

prevalences of bothmarkers were significantly higher at exacerbation that at remission stage of the disease

and so werein CAH than in chronic asymptomatic HBV carrier （AsC） with normal histology. Besides

the pre-valences were significantly higher in HBeAg positive group than in anti-HBe positive group.However

the polymerized human serum albumin binding activity and the preS2 were undoubtedlynot the same

as the prevalence of the latter was only 56.7% of the former.