Comparison of pre-S1 and pre-S2 proteins in hepatocytes with replication by in situ hybridization assay.

To compare the relationship of pre-S1 and pre-S2 proteins in hepatocytes with HBV replication, HBVDNA in situ hybridization was performed for a group of patients with chronic hepatitis by bio-probe, in conjunction with detection of intrahepatic HBsAg, HBcAg, pre-S1 and-S2 antigens. It was found that the expression of intrahepatic pre-s1 and pre-S2 proteins was visualized as cytoplasmic homogeneous and inclusion types, on some occasions as membranous localization. However, the positive rate for pre-S1 protein was up to 75% (15/20), being significantly higher than that of pre-S2 protein (35%; 7/20) in the same group (P less than 0.05). What in more important, the pre-S1 expression, rather than pre-s2, was in parallel with the presence of intrahepatic HBVDNA and HbcAg. All these findings suggest that the pre-S1 protein might be mainly expressed at the HBV replication phase, thus, to some extent, the detection of pre-S1 protein might complement HBe system and HBVDNA clinical routine.