Cryopreservation of feline red blood cells in liquid nitrogen using glycerol and hydroxyethyl starch

• Published in: Journal of feline medicine and surgery 2020-04, Vol.22 (4), p.366-375
• Main Authors: Hon, Marcelle, Thomovsky, Elizabeth J, Brooks, Aimee C, Johnson, Paula A
• Format: Article
• Language: English
• Subjects: Animals; Cats; Cryopreservation - methods; Cryopreservation - veterinary; Cryoprotective Agents - pharmacology; Dogs; Erythrocytes - cytology; Erythrocytes - drug effects; Glycerol - pharmacology; Hydroxyethyl Starch Derivatives - pharmacology; Nitrogen - chemistry; Original
• ISSN: 1098-612X; 1532-2750; 1532-2750
• DOI: 10.1177/1098612X19850932

Objectives The objective of this study was to evaluate the techniques and short-term effects of cryopreservation of feline red blood cells (RBCs) in liquid nitrogen using glycerol or hydroxyethyl starch (HES) as a cryoprotectant. Methods Feline RBCs were manually mixed with either 20% glycerol or 12.5% HES and frozen for 24 h in liquid nitrogen. The samples were thawed and glycerolized samples were manually washed. Success of the freeze/thaw process was determined by recovery rate of RBCs and evaluation of morphological changes using scanning electron microscopy (SEM). A unit of canine packed RBCs was also subjected to the same methodology to evaluate the cryopreservation handling technique. Results Feline RBCs preserved with 20% glycerol had a high recovery rate (94.23 ± 1.25%) immediately after thawing. However, the majority of the cells were lost during the washing process, with a final packed cell volume of