A comparative study of the effects of glycerol and hydroxyethyl starch in canine red blood cell cryopreservation.
Hydroxyethyl starch (HES) is a nonpenetrating extracellular cryoprotectant. In contrast to glycerol, it does not require labor-intensive removal from thawed red blood cells (RBCs) prior to transfusion. In this study, we compared glycerol and HES, and assessed HES as a substitute for glycerol in cryopreserved canine RBCs. The RBCs were preserved for 2 months in liquid nitrogen using a 20% (w/v) glycerol solution, and variable concentrations of HES solution. We evaluated the two cryoprotectants by the percentage of post-thaw hemolysis from the total free hemoglobin, saline stability, osmotic fragility, and by observing the erythrocyte morphology using a scanning electron microscope after thawing. The optimal concentration of HES was 12.5% (w/v) for the cryopreservation of canine RBCs. The thaw hemolysis, saline stability, and osmotic fragility index were 25.6 +/- 4.7%, 87.8 +/- 6.9%, and 0.445 +/- 0.024% NaCl respectively. These parameters resemble the results of RBCs frozen in a 20% (w/v) glycerol solution, which are 24.7 +/- 5.2%, 99.2 +/- 0.1%, and 0.485 +/- 0.023% NaCl respectively. From a morphological point of view, 12.5% (w/v) HES showed the best cryoprotection of RBCs compared to the other concentrations of HES. These results suggest that HES could be a possible substitute for glycerol for the cryopreservation of canine RBCs.
Kim
Heejaung
H
The United Graduate School of Veterinary Sciences, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-8515, Japan.
Tanaka
Shuhei
S
Une
Satoshi
S
Nakaichi
Munekazu
M
Sumida
Sajio
S
Taura
Yasuho
Y
D000818:Animals; D015925:Cryopreservation / Q000379:methods*; D004285:Dogs / Q000097:blood*; D004912:Erythrocytes / Q000187:drug effects* / Q000648:ultrastructure; D005990:Glycerol / Q000494:pharmacology*; D006461:Hemolysis / Q000187:drug effects; D006895:Hydroxyethyl Starch Derivatives / Q000494:pharmacology*; D008855:Microscopy, Electron, Scanning; D009584:Nitrogen
D006895:Hydroxyethyl Starch Derivatives; D009584:Nitrogen; D005990:Glycerol