title: Susceptibility to hyperosmotic stress-induced phosphatidylserine exposure increases during red blood cell storage.
abstract: BACKGROUND
  During storage of red blood cell (RBCs) before transfusion, RBCs undergo a series of structural and functional changes that include the exposure of phosphatidylserine (PS), a potent removal signal. It was postulated that, during blood bank storage, the susceptibility to stress-induced PS exposure increases, thereby rendering a considerable fraction of the RBCs susceptible to rapid removal after transfusion.
  
  
  METHODS
  RBCs were processed and stored following standard Dutch blood bank procedures. Samples were taken every week for up to 6 weeks and exposed to various stress conditions, such as hyperosmotic shock and energy depletion. The effect of these treatments on PS exposure was measured by flow cytometric analysis of annexin V binding. The same analyses were performed on RBCs that had been separated according to density using discontinuous Percoll gradients.
  
  
  RESULTS
  During storage under blood bank conditions, RBCs become increasingly susceptible to loss of phospholipid asymmetry induced by hyperosmotic shock and energy depletion. Especially the RBCs of higher densities, that have a smaller volume and an increased HbA1c content as is typical of aged RBCs, become increasingly susceptible with storage time.
  
  
  CONCLUSIONS
  During storage, RBCs develop an increased susceptibility to stress-induced loss of phospholipid asymmetry that is especially associated with an aging phenotype. This increased susceptibility may be responsible for the rapid disappearance of a considerable fraction of the RBCs during the first 24 hours after transfusion.
authors.affiliation: Department of Biochemistry and Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, Nijmegen, the Netherlands. g.bosman@ncmls.ru.nl
authors.forename: Giel J C G M
authors.initials: GJ
authors.lastname: Bosman
authors.forename: Judith C A
authors.initials: JC
authors.lastname: Cluitmans
authors.forename: Yvonne A M
authors.initials: YA
authors.lastname: Groenen
authors.forename: Jan M
authors.initials: JM
authors.lastname: Werre
authors.forename: Frans L A
authors.initials: FL
authors.lastname: Willekens
authors.forename: Vĕra M J
authors.initials: VM
authors.lastname: Novotný
mesh_terms: D017304:Annexin A5 / Q000378:metabolism; D000094902:Blood Banking / Q000379:methods; D001793:Blood Preservation / Q000379:methods*; D004734:Energy Metabolism / Q000502:physiology; D004910:Erythrocyte Membrane / Q000378:metabolism; D017707:Erythrocyte Transfusion; D004912:Erythrocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D005434:Flow Cytometry; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D009997:Osmotic Pressure / Q000502:physiology*; D010718:Phosphatidylserines / Q000378:metabolism*
chemical_list: D017304:Annexin A5; D006442:Glycated Hemoglobin; D010718:Phosphatidylserines; C517652:hemoglobin A1c protein, human