title: Direct ex vivo evaluation of long-lived protective antiviral memory B cell responses against hepatitis B virus.
abstract: BACKGROUND
  The frequency of protective antiviral memory B cells after hepatitis B virus (HBV) vaccination is unknown.
  
  
  METHODS
  A novel 2-step immunomagnetic protocol to assess the ex vivo frequency of protective HBV surface antigen (HBsAg)-specific memory B cells was used.
  
  
  RESULTS
  HBsAg-specific memory B cells were detected in vaccinated individuals, although at very low frequency (median, 0.2% of CD19(+) cells [range, 0%-4% of CD19(+) cells]). No correlation existed between the frequency of HBsAg-specific memory B cells and the corresponding serum antibody titer or B cell enzyme-linked immunosorbent spot findings.
  
  
  CONCLUSIONS
  Our results indicate sustained B cell-mediated protection against HBV despite waning antibody titers, which is consistent with clinical observations.
authors.affiliation: Peter Medawar Building for Pathogen Research, Nuffield Department of Clinical Medicine, Oxford University, Oxford, United Kingdom. s.ward1@uq.edu.au
authors.forename: Scott M
authors.initials: SM
authors.lastname: Ward
authors.forename: Prabhjeet
authors.initials: P
authors.lastname: Phalora
authors.forename: Daniel
authors.initials: D
authors.lastname: Bradshaw
authors.forename: Heike
authors.initials: H
authors.lastname: Leyendeckers
authors.forename: Paul
authors.initials: P
authors.lastname: Klenerman
mesh_terms: D015703:Antigens, CD / Q000032:analysis; D018941:Antigens, CD19 / Q000032:analysis; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000821:virology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002469:Cell Separation / Q000379:methods; D006509:Hepatitis B / Q000276:immunology*; D006514:Hepatitis B Surface Antigens / Q000032:analysis; D017325:Hepatitis B Vaccines; D006515:Hepatitis B virus / Q000276:immunology*; D006801:Humans; D007156:Immunologic Memory; D012016:Reference Values
chemical_list: D015703:Antigens, CD; D018941:Antigens, CD19; D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines