title: Evaluation of the sensitivity of red blood cell markers to detect photodynamic membrane damage.
abstract: BACKGROUND
  Photodynamic dyes have been used to investigate pathogen reduction methods in RBC suspensions, but treatment with sensitizers and light can produce unwanted membrane damage during routine blood bank storage. This study compares the relative sensitivity of three assays for detecting RBC membrane damage.
  
  
  METHODS
  RBCs were treated with dimethylmethylene blue and red light-emitting diode light under four conditions differing in photodynamic stringency and subsequently stored under refrigerated conditions for up to 42 days. Hemolysis, potassium release, and the apoptosis marker annexin V binding were assayed immediately after phototreatment and following storage.
  
  
  RESULTS
  In terms of increasing sensitivity for detecting photodynamic RBC membrane damage was enhanced ion leakage >> hemolysis > annexin V binding.
  
  
  CONCLUSIONS
  Although very stringent photodynamic treatment conditions generate annexin V-positive RBCs, the assay will not detect more subtle membrane damage that is readily detected by other well-established methods. In addition, many RBCs destined for photo-induced hemolysis later in storage are annexin V-negative throughout the storage period, suggesting that the two measures are not directly related.
authors.affiliation: Blood and Cell Therapy Development, American Red Cross, Biomedical Research and Development, Rockville, Maryland 20855, USA. wagners@usa.redcross.org
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Wagner
authors.forename: Andrey
authors.initials: A
authors.lastname: Skripchenko
authors.forename: Dedeene
authors.initials: D
authors.lastname: Thompson-Montgomery
authors.forename: Helen
authors.initials: H
authors.lastname: Awatefe
mesh_terms: D017304:Annexin A5 / Q000378:metabolism*; D015415:Biomarkers; D004910:Erythrocyte Membrane / Q000187:drug effects*; D004912:Erythrocytes / Q000378:metabolism; D006461:Hemolysis / Q000187:drug effects*; D006801:Humans; D010778:Photochemotherapy; D011188:Potassium / Q000378:metabolism*; D012680:Sensitivity and Specificity
chemical_list: D017304:Annexin A5; D015415:Biomarkers; D011188:Potassium