Farges E, Grebe R, Baumann M
Institute of Physiology, Medical Faculty, Technical University of Aachen, 52057 Aachen, Germany.
Clin Hemorheol Microcirc. 2002;27(1):1-11.
During storage at +4 degrees C, red blood cells undergo biochemical and physicochemical modifications, which alter their rheological characteristics especially the deformability. Even so until now not precisely defined deformability is undoubtedly a function of whole cell elasticity and viscosity. In a previous study we have investigated changes of elasticity of whole RBCs during a 6 weeks storage by quasi-static experiments using our Cell-Elastometer method. Since the changes in deformability we observed with that experimental approach have not been significant we extended the hard/software capabilities of this instrument to enable dynamic measurements also. We applied this modified hard-/software set-up to examine again changes in viscoelasticity of erythrocytes from concentrates during a six weeks storage at a blood bank. The cells were resuspended in CPD-SAG-M and stored at +4 degrees C. Quasi-static and dynamic experiments were performed on stored erythrocytes and showed for both significant changes in elasticity and viscoelasticity from the fourth week on. So it can be stated that due to our experimental results decrease in deformability of RBCs during storage occurs after a four weeks period of relative stability. To get further insight in changes of underlying or related biochemical properties according experiments have been performed in parallel. Especially the decrease in ATP showed a nearly parallel time course with a significant decrease after the 4th week. All other parameters especially the 2,3 DPG level showed a nearly linear de- or increase with time which are in accordance with the results of the additionally performed elongation experiments. Our quasi-static and dynamic deformability measurements have been proven to provide a simple and reliable tool to follow up erythrocyte senescence during storage where a pronounced change in mechanical properties may be used as an indicator for a change in bioviability. This has to be verified in further experiments.
在4℃储存期间，红细胞会经历生化和物理化学修饰，这会改变其流变学特性，尤其是可变形性。即便如此，到目前为止尚未精确定义的可变形性无疑是全细胞弹性和粘度的函数。在之前的一项研究中，我们使用细胞弹性仪方法通过准静态实验研究了全红细胞在6周储存期间的弹性变化。由于我们用该实验方法观察到的可变形性变化并不显著，我们扩展了该仪器的硬件/软件功能，使其也能够进行动态测量。我们应用这种改进后的硬件/软件设置，再次检测血库中浓缩红细胞在六周储存期间的粘弹性变化。细胞重悬于CPD-SAG-M中并在4℃储存。对储存的红细胞进行了准静态和动态实验，结果表明从第四周开始，弹性和粘弹性均发生了显著变化。因此可以说，根据我们的实验结果，红细胞在储存期间的可变形性下降发生在四周相对稳定期之后。为了进一步深入了解潜在或相关生化特性的变化，同时进行了相应实验。特别是ATP的下降显示出几乎平行的时间进程，在第4周后显著下降。所有其他参数，尤其是2,3-二磷酸甘油酸（2,3-DPG）水平随时间呈现几乎线性的下降或上升，这与额外进行的伸长实验结果一致。我们的准静态和动态可变形性测量已被证明是一种简单可靠的工具，可用于追踪储存期间红细胞的衰老情况，其中机械性能的显著变化可作为生物活性变化的指标。这一点必须在进一步的实验中得到验证。
