HBV-DNA and sFas, sFasL concentrations in serum of healthy HBsAg carriers

Increased HBV-DNA concentration is a prognostic factor of disease progression in chronic hepatitis B patients. Moreover, active hepatic inflammation during HBV replication influences apoptosis intensification. The aim of this study was to estimate occurrence of HBV replication among carriers of HBsAg. Furthermore, we analysed the correlation between HBV replication and HBeAg or anti-HBe presence as well as known apoptosis indicators--sFas and sFasL concentration.

The study included 34 HBV infected patients, aged 20-43 yrs defined as HBsAg healthy carriers. HBV-DNA was extracted from patients' serum using two different DNA isolation kits: the QIAamp DNA Mini Kit (QIAGEN Ltd, USA) and the Gene Elute Mammalian Genomic DNA Miniprep Kit (Sigma, USA). HBV-DNA concentration in serum was measured by RT-PCR based on TaqMan Universal Master Mix (Applied Biosystems). The detection limit of this system was as few as 10 HBV-DNA copies/mL of serum. HBV-DNA concentration was calculated from a linear standard curve obtained between 10 and 10(8) DNA copies/reaction. HBeAg and anti-HBe in serum were detected by MEIA method (ABBOTT, Germany). The concentration of sFas and sFasL in serum was-estimated by ELISA method (Bender MedSystems, Austria).

HBV active replication was detected in 79% HBsAg carriers. The HBV-DNA levels exceeding 10(5) copies/mL were observed in 64% patients. Among HBsAg carriers presenting HBeAg, HBV replication occurred more often and was more intensify than in HBsAg carriers presenting anti-HBe antibodies. The sFasL occurrence in serum of 56% HBsAg carriers shows an active apoptosis, independent from ALT and AST activity within normal ranges.