title: Age-matched lymphocyte subpopulation reference values in childhood and adolescence: application of exponential regression analysis.
abstract: BACKGROUND
  Normal values of lymphocyte subpopulations for healthy children and adults have been published in defined age groups exclusively, which results in difficult data interpretation for patients close to the limit of contiguous age group ranges. In addition, normal values for a number of lymphocyte subpopulations have not been established to date.
  
  
  OBJECTIVE
  The aim of this study was to develop a model which provides continuous age-dependent reference values. This model was applied for lymphocyte subpopulations such as naïve and memory T cells as well as their activation profile with diagnostic relevance in children and adults.
  
  
  METHODS
  A total of 100 blood samples, obtained from 80 healthy children and 20 adults were analysed by means of four colour-flow cytometry. Continuous age-dependent reference values were computed based on the residual values in an exponential regression model.
  
  
  RESULTS
  We calculated a continuous age-related regression model for both, absolute cell counts and percentages of CD3(+)CD4(+) T helper (T(H)) cells, CD3(+)CD8(+) cytotoxic T cells, CD56(+)CD3(-) natural killer (NK) cells, CD56(+)CD3(+) T cells, CD3(+)CD4(+)CD45RA(+) naïve T(H) cells, CD3(+)CD4(+)CD45RO(+) memory T(H) cells, CD3(+)CD8(+)CD45RA(+)CD28(+) naïve cytotoxic T cells, CD3(+)CD8(+)CD45RO(+) memory cytotoxic T cells, CD3(+)CD8(+)CD69(+) early activated cytotoxic T cells and CD3(+)CD8(+)HLA-DR(+) late activated cytotoxic T cells, respectively, to obtain reference values.
  
  
  CONCLUSIONS
  Based on an exponential regression model, the obtained reference values reflect the continuous maturation of lymphocyte subsets during childhood.
authors.affiliation: Paediatric Haematology, Oncology and Haemostaseology, Johann Wolfgang Goethe University Hospital, Frankfurt/Main, Germany. s@bine-huenecke.de
authors.forename: Sabine
authors.initials: S
authors.lastname: Huenecke
authors.forename: Michael
authors.initials: M
authors.lastname: Behl
authors.forename: Carla
authors.initials: C
authors.lastname: Fadler
authors.forename: Stefanie Y
authors.initials: SY
authors.lastname: Zimmermann
authors.forename: Konrad
authors.initials: K
authors.lastname: Bochennek
authors.forename: Lars
authors.initials: L
authors.lastname: Tramsen
authors.forename: Ruth
authors.initials: R
authors.lastname: Esser
authors.forename: Dieter
authors.initials: D
authors.lastname: Klarmann
authors.forename: Martina
authors.initials: M
authors.lastname: Kamper
authors.forename: Alexandra
authors.initials: A
authors.lastname: Sattler
authors.forename: Dorothee
authors.initials: D
authors.lastname: von Laer
authors.forename: Thomas
authors.initials: T
authors.lastname: Klingebiel
authors.forename: Thomas
authors.initials: T
authors.lastname: Lehrnbecher
authors.forename: Ulrike
authors.initials: U
authors.lastname: Koehl
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007223:Infant; D016131:Lymphocyte Subsets; D008297:Male; D012016:Reference Values; D012044:Regression Analysis; D055815:Young Adult