title: Diurnal rhythms in blood cell populations and the effect of acute sleep deprivation in healthy young men.
abstract: OBJECTIVE
  The sleep/wake cycle is accompanied by changes in circulating numbers of immune cells. The goal of this study was to provide an in-depth characterization of diurnal rhythms in different blood cell populations and to investigate the effect of acute sleep deprivation on the immune system, as an indicator of the body's acute stress response.
  
  
  METHODS
  Observational within-subject design.
  
  
  METHODS
  Home environment and Clinical Research Centre.
  
  
  METHODS
  15 healthy male participants aged 23.7 ± 5.4 (standard deviation) yr.
  
  
  METHODS
  Total sleep deprivation.
  
  
  RESULTS
  Diurnal rhythms of several blood cell populations were assessed under a normal sleep/wake cycle followed by 29 hr of extended wakefulness. The effect of condition (sleep versus sleep deprivation) on peak time and amplitude was investigated. Interindividual variation of, and the level of correlation between, the different cell populations was assessed. Comprehensive nonlinear curve fitting showed significant diurnal rhythms for all blood cell types investigated, with CD4 (naïve) cells exhibiting the most robust rhythms independent of condition. For those participants exhibiting significant diurnal rhythms in blood cell populations, only the amplitude of the granulocyte rhythm was significantly reduced by sleep deprivation. Granulocytes were the most diverse population, being most strongly affected by condition, and showed the lowest correlations with any other given cell type while exhibiting the largest interindividual variation in abundance.
  
  
  CONCLUSIONS
  Granulocyte levels and diurnal rhythmicity are directly affected by acute sleep deprivation; these changes mirror the body's immediate immune response upon exposure to stress.
authors: Department of Forensic Molecular Biology, Erasmus MC University Medical Centre Rotterdam, Rotterdam, The Netherlands. k.ackermann@erasmusmc.nl
authors: Katrin
authors: K
authors: Ackermann
authors: Victoria L
authors: VL
authors: Revell
authors: Oscar
authors: O
authors: Lao
authors: Elwin J
authors: EJ
authors: Rombouts
authors: Debra J
authors: DJ
authors: Skene
authors: Manfred
authors: M
authors: Kayser
mesh_terms: D000328:Adult; D018791:CD4 Lymphocyte Count; D002940:Circadian Rhythm / Q000502:physiology*; D005434:Flow Cytometry; D006098:Granulocytes / Q000502:physiology; D006801:Humans; D007958:Leukocyte Count; D007962:Leukocytes / Q000502:physiology; D018655:Lymphocyte Count; D008297:Male; D012892:Sleep Deprivation / Q000097:blood* / Q000503:physiopathology; D055815:Young Adult