title: Use of a booster dose of capsular group C meningococcal glycoconjugate vaccine to demonstrate immunologic memory in children primed with one or two vaccine doses in infancy.
abstract: Use of a polysaccharide vaccine challenge to demonstrate immunologic memory after priming with capsular group C meningococcal conjugate vaccines (MenCC) risks induction of immunologic hyporesponsiveness. For this reason, MenCC vaccines are now used as probes of immunologic memory, however, no studies have demonstrated their ability to distinguish primed from unprimed children.
  
  
  
  This study was part of a randomised controlled trial investigating the immunogenicity of a booster dose of the combined Haemophilus influenzae type b and MenC-tetanus toxoid vaccine (Hib-MenC-TT) in infants receiving reduced dose MenCC vaccine priming schedules (one MenC-CRM/MenC-TT or two MenC-CRM vaccine doses) compared with an unprimed group. Antibody kinetics were studied in a subset of 269 children by measuring changes in the MenC serum bactericidal antibody, using rabbit complement, (MenC rSBA) titres and MenC specific IgG memory B-cells before and at 6 and 28days following the 12month booster vaccination.
  
  
  
  At 6days after the 12monthMenCC vaccine, the rise in MenC rSBA titres and MenC specific IgG memory B-cells of the primed groups were significantly higher than the infant MenCC naïve group. Participants primed with one MenC-TT dose had the highest increase in MenC rSBA titres compared with all other groups. The MenC rSBA titres at the 28th compared with the 6th day after boosting was significantly higher in those primed with a single MenC-TT/MenC-CRM vaccine in infancy compared with those who were not primed or who were primed with two doses of the MenC-CRM vaccine.
  
  
  
  Immunologic memory can be demonstrated by a MenCC booster vaccination but is affected by the type and number of MenCC doses used for infant priming. The MenC rSBA responses can be used to demonstrate successful immunologic priming.
authors.affiliation: Malta Children's Vaccine Group, Mater Dei Hospital, Tal-Qroqq, Msida MSD 2090, Malta. Electronic address: dpace@go.net.mt.
authors.forename: David
authors.initials: D
authors.lastname: Pace
authors.affiliation: Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, UK.
authors.forename: Ameneh
authors.initials: A
authors.lastname: Khatami
authors.affiliation: Malta Children's Vaccine Group, Mater Dei Hospital, Tal-Qroqq, Msida MSD 2090, Malta.
authors.forename: Simon
authors.initials: S
authors.lastname: Attard-Montalto
authors.affiliation: Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK; Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, UK.
authors.forename: Merryn
authors.initials: M
authors.lastname: Voysey
authors.affiliation: Bristol Children's Vaccine Centre, University Hospitals Bristol NHS Foundation Trust & University of Bristol, Bristol, UK.
authors.forename: Adam
authors.initials: A
authors.lastname: Finn
authors.affiliation: Southampton NIHR Wellcome Trust Clinical Research Facility, University Hospital Southampton NHS Foundation Trust, Southampton, UK; Academic Unit of Clinical and Experimental Sciences, Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.
authors.forename: Saul N
authors.initials: SN
authors.lastname: Faust
authors.affiliation: St. Georges Vaccine Institute, St Georges, University of London, London, UK.
authors.forename: Paul T
authors.initials: PT
authors.lastname: Heath
authors.affiliation: Vaccine Evaluation Unit, Public Health England, Public Health Laboratory Manchester, Manchester Royal Infirmary, Manchester, UK.
authors.forename: Ray
authors.initials: R
authors.lastname: Borrow
authors.affiliation: Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, UK.
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Snape
authors.affiliation: Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, UK.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Pollard
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood*; D001770:Blood Bactericidal Activity; D005260:Female; D018073:Haemophilus Vaccines / Q000008:administration & dosage* / Q000276:immunology*; D006801:Humans; D007117:Immunization, Secondary / Q000379:methods*; D007074:Immunoglobulin G / Q000097:blood; D007156:Immunologic Memory; D007223:Infant; D008297:Male; D038542:Neisseria meningitidis, Serogroup C / Q000276:immunology*; D013745:Tetanus Toxoid / Q000008:administration & dosage* / Q000276:immunology*; D018074:Vaccines, Conjugate / Q000008:administration & dosage / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D018073:Haemophilus Vaccines; C527605:Hib-MenCY-TT vaccine; D007074:Immunoglobulin G; D013745:Tetanus Toxoid; D018074:Vaccines, Conjugate
keywords: Capsular group C N. meningitidis; Immunologic memory; MenC glycoconjugate vaccines; MenC infant priming