Background: RBCs can be frozen with either the high-glycerol method (HGM) or the low-glycerol method (LGM). To date, the use of frozen RBCs is hampered by a 24-hour outdating period after thawing. A closed washing system (ACP 215) may solve this problem.
Study design and methods: We compared the effects of high- (40%) and low-glycerol (19%) concentration, with and without freezing (at -80 degrees C for HGM, -196 degrees C for LGM) on the in vitro quality of RBCs after deglycerolization with the closed washing system and during storage at 4 degrees C in SAGM after thawing.
Results: Glycerol treatment by itself induced hemolysis during processing, which was more pronounced in HGM cells. The freeze-thaw-wash process decreased the stability of RBCs, particularly in LGM cells during storage after thawing. In contrast to LGM cells, in HGM cells no additional effect of freeze or thaw on stability of washed cells was seen during the first week of storage after thawing. Changes in osmotic resistance and cellular metabolism could not explain the observed differences in RBC stability.
Conclusion: The closed washing system is able to process both high- and low-glycerol-treated RBCs. Stability after washing during cold storage in SAGM, as measured by hemolysis, is better for HGM cells as compared to LGM cells.