title: Comparison of neonatal T regulatory cell function in Papua New Guinean and Australian newborns.
abstract: BACKGROUND
  Environmental changes, including declining microbial exposure, have been linked with the rising incidence of allergic and autoimmune diseases in 'western' populations. This potentially occurs by altering early development of immuno-regulatory pathways including T regulatory cells (T(reg)). There is now increasing evidence that such conditioning begins in utero.
  
  
  METHODS
  We compared neonatal T(reg) from children born under typical western conditions (Australia, AUS) with those of neonates born under more traditional conditions of high microbial burden (Papua New Guinea, PNG).
  
  
  RESULTS
  The frequency of neonatal T(reg), defined as CD4(+) Foxp3(+) CD127(-) CD25(+/high) was found to be higher in the cord blood of AUS compared to PNG newborns. However, cord T(reg) suppressive function in a small subset of children was qualitatively similar between PNG and AUS newborns in both a T(reg) depletion assay and a T(reg) supplementation assay.
  
  
  CONCLUSIONS
  These findings do not support the hypothesis that living in a 'western' versus more traditional environment leads to poor induction or suppressive function of neonatal T(reg). However, environmentally-induced immuno-regulation may potentially occur via alternative mechanisms in PNG newborns that should now be investigated further.
authors.affiliation: Telethon Institute for Child Health Research, Centre for Child Health Research, University of Western Australia, Perth, Australia.
authors.forename: Joanne G
authors.initials: JG
authors.lastname: Lisciandro
authors.forename: Susan L
authors.initials: SL
authors.lastname: Prescott
authors.forename: Marie G
authors.initials: MG
authors.lastname: Nadal-Sims
authors.forename: Catherine J
authors.initials: CJ
authors.lastname: Devitt
authors.forename: William
authors.initials: W
authors.lastname: Pomat
authors.forename: Peter M
authors.initials: PM
authors.lastname: Siba
authors.forename: Patrick G
authors.initials: PG
authors.lastname: Holt
authors.forename: Deborah
authors.initials: D
authors.lastname: Strickland
authors.forename: Anita H J
authors.initials: AH
authors.lastname: van den Biggelaar
mesh_terms: D001315:Australia; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007231:Infant, Newborn / Q000097:blood / Q000276:immunology*; D008297:Male; D010219:Papua New Guinea; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*