Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Spain; Master's and Doctoral Degree Programs in Rehabilitation Sciences, Nove de Julho University, Sao Paulo, Brazil.
J Biomed Mater Res A. 2014 Feb;102(2):413-9. doi: 10.1002/jbm.a.34708. Epub 2013 May 18.
Lung bioengineering based on decellularized organ scaffolds is a potential alternative for transplantation. Freezing/thawing, a usual procedure in organ decellularization and storage could modify the mechanical properties of the lung scaffold and reduce the performance of the bioengineered lung when subjected to the physiological inflation-deflation breathing cycles. The aim of this study was to determine the effects of repeated freezing/thawing on the mechanical properties of decellularized lungs in the physiological pressure-volume regime associated with normal ventilation. Fifteen mice lungs (C57BL/6) were decellularized using a conventional protocol not involving organ freezing and based on sodium dodecyl sulfate detergent. Subsequently, the mechanical properties of the acellular lungs were measured before and after subjecting them to three consecutive cycles of freezing/thawing. The resistance (RL ) and elastance (EL ) of the decellularized lungs were computed by linear regression fitting of the recorded signals (tracheal pressure, flow, and volume) during mechanical ventilation. RL was not significantly modified by freezing-thawing: from 0.88 ± 0.37 to 0.90 ± 0.38 cmH2 O·s·mL(-1) (mean ± SE). EL slightly increased from 64.4 ± 11.1 to 73.0 ± 16.3 cmH2 O·mL(-1) after the three freeze-thaw cycles (p = 0.0013). In conclusion, the freezing/thawing process that is commonly used for both organ decellularization and storage induces only minor changes in the ventilation mechanical properties of the organ scaffold.
基于脱细胞器官支架的肺生物工程是移植的一种潜在替代方法。冷冻/解冻是器官脱细胞和储存过程中的常用程序，可能会改变肺支架的机械性能，并降低生物工程肺在经受生理充气-放气呼吸循环时的性能。本研究的目的是确定在与正常通气相关的生理压力-容积范围内，反复冷冻/解冻对脱细胞肺的机械性能的影响。使用不涉及器官冷冻且基于十二烷基硫酸钠去污剂的常规方案对 15 只 C57BL/6 小鼠肺进行脱细胞处理。随后，在对无细胞肺进行三次连续冷冻/解冻循环后，测量其机械性能。通过对机械通气过程中记录的信号（气管压力、流量和体积）进行线性回归拟合，计算脱细胞肺的阻力（RL）和顺应性（EL）。冷冻-解冻后 RL 无明显变化：从 0.88±0.37 增加到 0.90±0.38cmH2O·s·mL(-1)（平均值±SE）。在经过三个冷冻-解冻循环后，EL 从 64.4±11.1 略微增加到 73.0±16.3cmH2O·mL(-1)（p=0.0013）。总之，常用于器官脱细胞和储存的冷冻/解冻过程仅会引起器官支架通气机械性能的微小变化。
