title: Effect of early carriage of Streptococcus pneumoniae on the development of pneumococcal protein-specific cellular immune responses in infancy.
abstract: BACKGROUND
  The aim of this study was to examine the relationship between nasopharyngeal pneumococcal colonization in early life and the subsequent development of pneumococcal-specific T cell responses.
  
  
  METHODS
  Pernasal swabs were collected from Papua New Guinean infants at the ages of 1 and 2 weeks (n = 279). At 9 months, in vitro cellular immune responses to choline-binding protein A (n = 132), pneumococcal surface protein A (n = 132), pneumolysin (n = 99), and the pneumococcal conjugate vaccine carrier CRM197 were determined. Responses were compared based on the children's carriage status within the first 2 weeks of life.
  
  
  RESULTS
  Within the first 2 weeks of life, 40% of the study children carried Streptococcus pneumoniae. Early carriage was associated with lower interferon-γ and interleukin 10 responses to pneumococcal proteins at age 9 months when children had not received pneumococcal conjugate vaccines during the study period.
  
  
  CONCLUSIONS
  Early pneumococcal carriage may result in enhanced disease susceptibility and suboptimal vaccine responses by modulating the development of pneumococcal immune responses.
authors.affiliation: Division of Cell Biology, Telethon Institute for Child Health Research, Centre for Child Health Research, University of Western Australia, Perth WA, Australia. Anita.vandenBiggelaar@Crucell.com
authors.forename: Anita H J
authors.initials: AH
authors.lastname: van den Biggelaar
authors.forename: William S
authors.initials: WS
authors.lastname: Pomat
authors.forename: Suparat
authors.initials: S
authors.lastname: Phuanukoonnon
authors.forename: Audrey
authors.initials: A
authors.lastname: Michael
authors.forename: Celestine
authors.initials: C
authors.lastname: Aho
authors.forename: Marie A
authors.initials: MA
authors.lastname: Nadal-Sims
authors.forename: Catherine J
authors.initials: CJ
authors.lastname: Devitt
authors.forename: Peter A
authors.initials: PA
authors.lastname: Jacoby
authors.forename: Belinda J
authors.initials: BJ
authors.lastname: Hales
authors.forename: Wendy-Anne
authors.initials: WA
authors.lastname: Smith
authors.forename: Tim
authors.initials: T
authors.lastname: Mitchell
authors.forename: Selma
authors.initials: S
authors.lastname: Wiertsema
authors.forename: Peter
authors.initials: P
authors.lastname: Richmond
authors.forename: Peter
authors.initials: P
authors.lastname: Siba
authors.forename: Patrick G
authors.initials: PG
authors.lastname: Holt
authors.forename: Deborah
authors.initials: D
authors.lastname: Lehmann
mesh_terms: D000942:Antigens, Bacterial / Q000276:immunology*; D001426:Bacterial Proteins / Q000276:immunology*; D002353:Carrier State / Q000276:immunology*; D004198:Disease Susceptibility; D005260:Female; D006801:Humans; D007111:Immunity, Cellular; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009305:Nasopharynx / Q000382:microbiology; D010219:Papua New Guinea; D022242:Pneumococcal Vaccines / Q000008:administration & dosage / Q000276:immunology; D011247:Pregnancy; D013290:Streptococcal Infections / Q000276:immunology*; D013296:Streptococcus pneumoniae / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D022242:Pneumococcal Vaccines