Department of Chemistry, University of Ottawa, Ottawa, ON, K1N 6N5, Canada.
Canadian Blood Services, Centre of Innovation, 8249-114 Street NW, Edmonton, AB, T6G 2R8, Canada.
Sci Rep. 2016 Mar 29;6:23619. doi: 10.1038/srep23619.
During cryopreservation, ice recrystallization is a major cause of cellular damage. Conventional cryoprotectants such as dimethyl sulfoxide (DMSO) and glycerol function by a number of different mechanisms but do not mitigate or control ice recrystallization at concentrations utilized in cryopreservation procedures. In North America, cryopreservation of human red blood cells (RBCs) utilizes high concentrations of glycerol. RBC units frozen under these conditions must be subjected to a time-consuming deglycerolization process after thawing in order to remove the glycerol to <1% prior to transfusion thus limiting the use of frozen RBC units in emergency situations. We have identified several low molecular mass ice recrystallization inhibitors (IRIs) that are effective cryoprotectants for human RBCs, resulting in 70-80% intact RBCs using only 15% glycerol and slow freezing rates. These compounds are capable of reducing the average ice crystal size of extracellular ice relative to a 15% glycerol control validating the positive correlation between a reduction in ice crystal size and increased post-thaw recovery of RBCs. The most potent IRI from this study is also capable of protecting frozen RBCs against the large temperature fluctuations associated with transient warming.
在冷冻保存过程中，冰晶重结晶是导致细胞损伤的主要原因。传统的冷冻保护剂，如二甲基亚砜（DMSO）和甘油，通过多种不同的机制发挥作用，但在冷冻保存过程中使用的浓度下，它们既不能减轻也不能控制冰晶重结晶。在北美，人类红细胞（RBC）的冷冻保存利用高浓度的甘油。在这些条件下冷冻的 RBC 单位在解冻后必须经过耗时的去甘油化过程，以在输血前将甘油去除到<1%，从而限制了在紧急情况下使用冷冻 RBC 单位。我们已经确定了几种低分子量的冰晶重结晶抑制剂（IRIs），它们是人类 RBC 的有效冷冻保护剂，仅使用 15%的甘油和缓慢的冷冻速率，就可以使 70-80%的 RBC 保持完整。这些化合物能够降低细胞外冰的平均冰晶尺寸，与 15%甘油对照相比，验证了冰晶尺寸减小与 RBC 解冻后恢复增加之间的正相关关系。本研究中最有效的 IRI 还能够保护冷冻 RBC 免受与短暂升温相关的大温度波动的影响。
