PDF(Pubmed)
Abstract：
Ex vivo labeling with 51 chromium represents the standard method to determine red blood cell (RBC) survival after transfusion. Limitations and safety concerns spurred the development of alternative methods, including biotinylated red blood cells (BioRBC).
Autologous units of whole blood were divided equally into two bags and stored under standard blood bank conditions at 2 to 6°C (N = 4 healthy adult volunteers). One bag was biotinylated (15 μg/ml) on storage days 5 to 7 (fresh) and the other was biotinylated (3 μg/ml) on days 35 to 42 (aged). The proportion of circulating BioRBC was measured serially, and cell-surface biotin was quantified with reference to molecules of equivalent soluble fluorochrome. Clearance kinetics were modeled by RBC age distribution at infusion (Gaussian vs. uniform) and decay over time (constant vs. exponential).
Data were consistent with biphasic exponential clearance of cells of uniform age. Our best estimate of BioRBC clearance (half-life [T1/2 ]) was 49.7 ± 1.2 days initially, followed by more rapid clearance 82 days after transfusion (T1/2 = 15.6 ± 0.6 days). As BioRBC aged in vivo, molecules of equivalent soluble fluorochrome declined with a T1/2 of 122 ± 9 days, suggesting gradual biotin cleavage. There were no significant differences between the clearance of fresh and aged BioRBC.
Similar clearance kinetics of fresh and aged BioRBC may be due to the extensive washing required during biotinylation. Survival kinetics consistent with cells with uniform rather than Gaussian or other non-uniform age distributions suggest that washing, and potentially RBC culling, may extend the storage life of RBC products.
Autologous units of whole blood were divided equally into two bags and stored under standard blood bank conditions at 2 to 6°C (N = 4 healthy adult volunteers). One bag was biotinylated (15 μg/ml) on storage days 5 to 7 (fresh) and the other was biotinylated (3 μg/ml) on days 35 to 42 (aged). The proportion of circulating BioRBC was measured serially, and cell-surface biotin was quantified with reference to molecules of equivalent soluble fluorochrome. Clearance kinetics were modeled by RBC age distribution at infusion (Gaussian vs. uniform) and decay over time (constant vs. exponential).
Data were consistent with biphasic exponential clearance of cells of uniform age. Our best estimate of BioRBC clearance (half-life [T1/2 ]) was 49.7 ± 1.2 days initially, followed by more rapid clearance 82 days after transfusion (T1/2 = 15.6 ± 0.6 days). As BioRBC aged in vivo, molecules of equivalent soluble fluorochrome declined with a T1/2 of 122 ± 9 days, suggesting gradual biotin cleavage. There were no significant differences between the clearance of fresh and aged BioRBC.
Similar clearance kinetics of fresh and aged BioRBC may be due to the extensive washing required during biotinylation. Survival kinetics consistent with cells with uniform rather than Gaussian or other non-uniform age distributions suggest that washing, and potentially RBC culling, may extend the storage life of RBC products.
摘要：
背景：用51铬进行离体标记代表了确定输血后红细胞（RBC）存活的标准方法。局限性和安全问题刺激了替代方法的发展，包括生物素化红细胞（BioRBC）。
方法：将全血的自体单位平均分成两袋，并在2至6°C的标准血库条件下储存（N=4名健康成年志愿者）。一个袋子在储存第5至7天(新鲜)被生物素化(15μg/ml),另一个在第35至42天(老化)被生物素化(3μg/ml)。连续测量循环BioRBC的比例，细胞表面生物素的定量参照等效可溶性荧光染料的分子。通过输注时红细胞年龄分布对清除率动力学进行建模(高斯与均匀)和随时间的衰减(常数与指数)。
结果：数据与同龄细胞的双相指数清除一致。我们对BioRBC清除率的最佳估计（半衰期[T1/2]）最初为49.7±1.2天，输血后82天更快清除（T1/2=15.6±0.6天）。随着BioRBC在体内老化，等效可溶性荧光染料分子以T1/2为122±9天下降，提示生物素逐渐裂解。新鲜和老化的BioRBC的清除率之间没有显着差异。
结论:新鲜和老化的BioRBC的类似清除动力学可能是由于在生物素化期间需要大量洗涤。与具有均匀而非高斯或其他非均匀年龄分布的细胞一致的生存动力学表明，洗涤，潜在的红细胞剔除，可延长RBC产品的储存寿命。
方法：将全血的自体单位平均分成两袋，并在2至6°C的标准血库条件下储存（N=4名健康成年志愿者）。一个袋子在储存第5至7天(新鲜)被生物素化(15μg/ml),另一个在第35至42天(老化)被生物素化(3μg/ml)。连续测量循环BioRBC的比例，细胞表面生物素的定量参照等效可溶性荧光染料的分子。通过输注时红细胞年龄分布对清除率动力学进行建模(高斯与均匀)和随时间的衰减(常数与指数)。
结果：数据与同龄细胞的双相指数清除一致。我们对BioRBC清除率的最佳估计（半衰期[T1/2]）最初为49.7±1.2天，输血后82天更快清除（T1/2=15.6±0.6天）。随着BioRBC在体内老化，等效可溶性荧光染料分子以T1/2为122±9天下降，提示生物素逐渐裂解。新鲜和老化的BioRBC的清除率之间没有显着差异。
结论:新鲜和老化的BioRBC的类似清除动力学可能是由于在生物素化期间需要大量洗涤。与具有均匀而非高斯或其他非均匀年龄分布的细胞一致的生存动力学表明，洗涤，潜在的红细胞剔除，可延长RBC产品的储存寿命。
