title: Pertussis circulation has increased T-cell immunity during childhood more than a second acellular booster vaccination in Dutch children 9 years of age.
abstract: Here we report the first evaluation of T-cell responses upon a second acellular pertussis booster vaccination in Dutch children at 9 years of age, 5 years after a preschool booster vaccination. Blood samples of children 9 years of age were studied longitudinally until 1 year after the second aP booster and compared with those after the first aP booster in children 4 and 6 years of age from a cross-sectional study. After stimulation with pertussis-vaccine antigens, Th1, Th2 and Th17 cytokine responses were measured and effector memory cells (CCR7-CD45RA-) were characterized by 8-colour FACS analysis. The second aP booster vaccination at pre-adolescent age in wP primed individuals did increase pertussis-specific Th1 and Th2 cytokine responses. Noticeably, almost all T-cell responses had increased with age and were already high before the booster vaccination at 9 years of age. The enhancement of T-cell immunity during the 5 year following the booster at 4 years of age is probably caused by natural boosting due to the a high circulation of pertussis. However, the incidence of pertussis is high in adolescents and adults who have only received the Dutch wP vaccine during infancy and no booster at 4 years of age. Therefore, an aP booster vaccination at adolescence or later in these populations might improve long-term immunity against pertussis and reduce the transmission to the vulnerable newborns.
  
  
  BACKGROUND
  Controlled-Trials.com ISRCTN64117538.
authors.affiliation: Laboratory for Infectious Disease and Perinatal Screening, Center for Infectious Diseases Control, National Institute for Public Health, Bilthoven, the Netherlands.
authors.forename: Rose-Minke
authors.initials: RM
authors.lastname: Schure
authors.forename: Lia
authors.initials: L
authors.lastname: de Rond
authors.forename: Kemal
authors.initials: K
authors.lastname: Oztürk
authors.forename: Lotte
authors.initials: L
authors.lastname: Hendrikx
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Sanders
authors.forename: Guy
authors.initials: G
authors.lastname: Berbers
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Buisman
mesh_terms: D017252:CD3 Complex / Q000276:immunology; D015704:CD4 Antigens / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D016207:Cytokines / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D006801:Humans; D007117:Immunization, Secondary; D007156:Immunologic Memory; D009426:Netherlands / Q000453:epidemiology; D013601:T-Lymphocytes / Q000276:immunology*; D014917:Whooping Cough / Q000453:epidemiology* / Q000276:immunology / Q000378:metabolism
chemical_list: D017252:CD3 Complex; D015704:CD4 Antigens; D016207:Cytokines