Relationg of HBV P gene quasispecies mutants and adefovir dipivoxil in the treatment of HBeAg-positive chronic hepatitis B

Objective To investigate the relationship between hepatitis B virus P gene (HBV-P) quasispecies mutants and adefovir dipivoxil in the treatment of HBeAg-positive chronic hepatitis B.Methods Nested-PCR(NT-PCR)amplification of HBV-P gene in the coverage zone B zone-E gene fragment sequences,PCR product was purified and directly sequenced to assess the HBV quasispecies complexity.The difference of amino acid of part P gene in HBV DNA was analyzed,and the mutation was classified by using CLUSTAL V method with DNA STAR software.128 patients received adefovir dipivoxil 10 mg once daily for 24 to 96 weeks.Therapeutic effect evaluation involved the serum HBV DNA level,HBeAg sero-conversion and biochemical response.Analysis the relationship between HBV-P quasispecies and nucleoside analogues treatment effect among patients with the long term complete responders (CRL),part responders (PR) and non responders (NR) at the onset,48 weeks and 96weeks of adefovir dipivoxil treatment.Results Of 128 patients received adefovir dipivoxil for two years,23 were CRL,86 were PR,and 19 were NR.Normal alanine amino transferas (ALT) was seen in 61.4 % patients(78/128);HBeAg sero-conversion in 21.9% patients(27/128);and HBV DNA negative in 50.8%(65/128).7 patients had resistance mutation,4 were rtn236T,2 were rtA181V,and another were rtN236T and rtA181V resistance mutation.The complexity and heterogeneity of quasispecies of this region were higher in adefovir dipivoxil treatment than no treatment,and so in the non responders groups than in long term complete responders.All the quasispecies were different among the three groups during treatment of adefovir dipivoxil.The quasispecies mutation was significantly different between the group CRL and NR on the 24th,48th week of treatment (P0.001).Conclusion There is a quasispecies nature of HBV-P gene in CHB patient.The quasispecies of this region may change dynamically with the changes of activity of hepatitis in the CHB patient.The complexity and heterogeneity of quasispecies of this region were low at the begin time points of adefovir dipivoxil treatment,while they became relatively high after a certain period of treatment and gradually went higher as time accumulates.The complexity of HBV quasispecies was correlated to adefovir dipivoxil in the treatment HBeAg-positive chronic hepatitis B.