title: Red blood cell processing for cryopreservation: from fresh blood to deglycerolization.
abstract: BACKGROUND
  Cryostorage of red blood cells (RBCs) represents a valid alternative to liquid storage, since units can be preserved safely for at least a decade while conserving RBC viability. While cryostorage has attracted a great deal of attention clinically, little is known about the biochemistry and physiology of cryostored erythrocyte concentrates.
  
  
  METHODS
  In the present study, we investigated cryostorage of RBCs through monitoring of cell processing steps (from fresh blood, to glycerolization, thawing and deglycerolization/washing) through repeated assays of standard parameters (MCV, RDW-SD) and scanning electron microscopy.
  
  
  RESULTS
  Cell processing for cryostorage resulted in increased RBC volumes. Shape alterations caused an increase in osmotic fragility and permeability to ions. A significant pH drop was observed which could not to be attributed to a higher metabolic rate, since the levels of lactate did not show substantial fluctuation during the cell processing steps tested in this study. Membrane anomalies are likely related to the hemolysis observed which preferentially affected the densest and oldest cell sub-populations, as confirmed by means of discontinuous density gradients.
  
  
  CONCLUSIONS
  Our results indicate that cryostorage itself in presence of glycerol does not significantly affect RBCs. Most of the alterations observed were related to cell processing and, in particular, to the increase of cytosolic glycerol as a consequence of the glycerolyzation step. Further studies might profitably investigate replacing glycerol with non-penetrating cryoprotectants.
authors.affiliation: Department of Environmental Sciences, University of Tuscia, Largo dell'Università, snc, 01100 Viterbo, Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: Pallotta
authors.forename: Gian Maria
authors.initials: GM
authors.lastname: D'Amici
authors.forename: Angelo
authors.initials: A
authors.lastname: D'Alessandro
authors.forename: Roberto
authors.initials: R
authors.lastname: Rossetti
authors.forename: Lello
authors.initials: L
authors.lastname: Zolla
mesh_terms: D001793:Blood Preservation / Q000379:methods*; D015925:Cryopreservation / Q000379:methods*; D004909:Erythrocyte Indices; D004912:Erythrocytes / Q000378:metabolism / Q000648:ultrastructure; D005990:Glycerol / Q000378:metabolism; D006801:Humans
chemical_list: D005990:Glycerol