To assess the significance of
pre-S proteins expression during
chronic hepatitis B virus (HBV)
infection, we developed a sensitive labeled
avidin biotin ELISA to detect pre-S1 and pre-S2
proteins. In serum specimens from 80 patients with chronic
liver disease, the frequency of pre-S1 and S2
proteins was 53.7% and 47.5%, respectively. Furthermore, it reached 87.8% and 77.6%, respectively, in cases with chronic HBV
infection, indicating that
pre-S proteins are usually expressed in sera with chronic HBV
infection. We found that the expression of
pre-S proteins is closely associated with HBV replicating markers, such as HBV
DNA,
HBcAg and
HBeAg, in sera of patients with chronic HBV
infection. Both pre-S1 and S2
proteins were often concurrently expressed in liver and serum with chronic HBV
infection. However, the frequency was slightly higher in liver than in serum, suggesting that it may be clinically valuable to detect
pre-S proteins in serum and liver simultaneously to determine the status of HBV
infection. Our results also indicated that
pre-S proteins expression in serum can serve as markers of HBV
infection, but cannot be used to estimate the severity and activity of hepatic pathology.