title: Refined characterization and reference values of the pediatric T- and B-cell compartments.
abstract: Work in the past years has led to a refined phenotypical description of functionally distinct T- and B-cell subsets. Since both lymphocyte compartments are established and undergo dramatic changes during childhood, redefined pediatric reference values of both compartments are needed. In a cohort of 145 healthy children, aged 0-18 years, the relative and absolute numbers of the various T- and B-cell subsets were determined. In addition, we found that besides thymic output, naive (CD27(+)CD45RO(-)) T-cell proliferation contributed significantly to the establishment of the naive T-cell compartment. At birth, regulatory (CD25(+)CD127(-)CD4(+)) T cells (Tregs) mainly had a naive (CD27(+)CD45RO(-)) phenotype whereas 'memory or effector-like' (CD45RO(+)) Tregs accumulated slowly during childhood. Besides the CD27(+)IgM(+)IgD(+) memory B-cell population, the recently identified CD27(-)IgG(+) and CD27(-)IgA(+) memory B-cell populations were already present at birth. These data provide reference values of the T- and B-cell compartments during childhood for studies of immunological disorders or immune reconstitution in children.
authors: Department of Immunology, University Medical Center Utrecht, Lundlaan 6, PO Box 85090, 3508 AB Utrecht, The Netherlands.
authors: R
authors: R
authors: van Gent
authors: C M
authors: CM
authors: van Tilburg
authors: E E
authors: EE
authors: Nibbelke
authors: S A
authors: SA
authors: Otto
authors: J F
authors: JF
authors: Gaiser
authors: P L
authors: PL
authors: Janssens-Korpela
authors: E A M
authors: EA
authors: Sanders
authors: J A M
authors: JA
authors: Borghans
authors: N M
authors: NM
authors: Wulffraat
authors: M B
authors: MB
authors: Bierings
authors: A C
authors: AC
authors: Bloem
authors: K
authors: K
authors: Tesselaar
mesh_terms: D000293:Adolescent; D016175:B-Lymphocyte Subsets / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005312:Fetal Blood / Q000276:immunology; D006801:Humans; D007154:Immune System Diseases / Q000097:blood*; D007223:Infant; D007231:Infant, Newborn; D018655:Lymphocyte Count; D012016:Reference Values; D016176:T-Lymphocyte Subsets / Q000276:immunology*