title: Hepatitis B virus e antigen loss during adefovir dipivoxil therapy is associated with enhanced virus-specific CD4+ T-cell reactivity.
abstract: Weak T-cell reactivity to hepatitis B virus (HBV) is thought to be the dominant cause for chronic HBV infection. Treatment with adefovir dipivoxil (ADV) increases the rate of HBV e antigen (HBeAg) loss; however, the immune mechanisms associated with this treatment response are not understood. Serial analysis of HBV-specific CD4+ T-cell reactivity was performed during 48 weeks of therapy with ADV and correlated with treatment outcome for 19 HBeAg-positive patients receiving ADV (n = 13) or the placebo (n = 6). We tested T-cell reactivity to HBV at seven protocol time points by proliferation, cytokine production, and enzyme-linked immunospot assays. A panel of serum cytokines was quantitated by cytokine bead array. ADV-treated patients showed increased CD4+ T-cell responses to HBV and lower serum levels of cytokines compared to those of placebo-treated patients. Enhanced CD4+ T-cell reactivity to HBV, which peaked at treatment week 16, was confined to a subgroup of ADV-treated patients who achieved greater viral suppression (5.3 +/- 0.3 log(10) copies/ml [mean +/- standard error of the mean {SEM}] serum HBV DNA reduction from baseline) and HBeAg loss, but not to ADV-treated patients with moderate (3.4 +/- 0.2 log(10) copies/ml [mean +/- SEM]) viremia reduction who remained HBeAg positive or to patients receiving the placebo. In conclusion, T-cell reactivity to HBV increases in a proportion of ADV-treated patients and is associated with greater suppression of HBV replication and HBeAg loss.
authors.affiliation: Institute of Hepatology, University College London, 69-75 Chenies Mews, London WC1E 6HX, United Kingdom.
authors.forename: Helen
authors.initials: H
authors.lastname: Cooksley
authors.forename: Shilpa
authors.initials: S
authors.lastname: Chokshi
authors.forename: Yafit
authors.initials: Y
authors.lastname: Maayan
authors.forename: Heiner
authors.initials: H
authors.lastname: Wedemeyer
authors.forename: Pietro
authors.initials: P
authors.lastname: Andreone
authors.forename: Richard
authors.initials: R
authors.lastname: Gilson
authors.forename: Thomas
authors.initials: T
authors.lastname: Warnes
authors.forename: Simona
authors.initials: S
authors.lastname: Paganin
authors.forename: Fabien
authors.initials: F
authors.lastname: Zoulim
authors.forename: David
authors.initials: D
authors.lastname: Frederick
authors.forename: Avidan U
authors.initials: AU
authors.lastname: Neumann
authors.forename: Carol L
authors.initials: CL
authors.lastname: Brosgart
authors.forename: Nikolai V
authors.initials: NV
authors.lastname: Naoumov
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D000328:Adult; D000998:Antiviral Agents / Q000627:therapeutic use*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D004279:DNA, Viral / Q000097:blood; D005260:Female; D006513:Hepatitis B e Antigens / Q000097:blood*; D006515:Hepatitis B virus / Q000187:drug effects / Q000276:immunology; D019694:Hepatitis B, Chronic / Q000188:drug therapy* / Q000821:virology; D006801:Humans; D008213:Lymphocyte Activation / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D063065:Organophosphonates / Q000627:therapeutic use*; D018894:Reverse Transcriptase Inhibitors / Q000627:therapeutic use*; D016896:Treatment Outcome; D014779:Virus Replication
chemical_list: D000998:Antiviral Agents; D004279:DNA, Viral; D006513:Hepatitis B e Antigens; D063065:Organophosphonates; D018894:Reverse Transcriptase Inhibitors; D000225:Adenine; C106812:adefovir dipivoxil