1 Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona , Barcelona, Spain .
Tissue Eng Part C Methods. 2014 May;20(5):412-22. doi: 10.1089/ten.TEC.2013.0325. Epub 2013 Nov 6.
Lung bioengineering, a novel approach to obtain organs potentially available for transplantation, is based on decellularizing donor lungs and seeding natural scaffolds with stem cells. Various physicochemical protocols have been used to decellularize lungs, and their performance has been evaluated in terms of efficient decellularization and matrix preservation. No data are available, however, on the effect of different decellularization procedures on the local stiffness of the acellular lung. This information is important since stem cells directly sense the rigidity of the local site they are engrafting to during recellularization, and it has been shown that substrate stiffness modulates cell fate into different phenotypes. The aim of this study was to assess the effects of the decellularization procedure on the inhomogeneous local stiffness of the acellular lung on five different sites: alveolar septa, alveolar junctions, pleura, and vessels' tunica intima and tunica adventitia. Local matrix stiffness was measured by computing Young's modulus with atomic force microscopy after decellularizing the lungs of 36 healthy rats (Sprague-Dawley, male, 250-300 g) with four different protocols with/without perfusion through the lung circulatory system and using two different detergents (sodium dodecyl sulfate [SDS] and 3-[(3-cholamidopropyl) dimethylammonio]-1-propanesulfonate [CHAPS]). The local stiffness of the acellular lung matrix significantly depended on the site within the matrix (p<0.001), ranging from ∼ 15 kPa at the alveolar septum to ∼ 60 kPa at the tunica intima. Acellular lung stiffness (p=0.003) depended significantly, albeit modestly, on the decellularization process. Whereas perfusion did not induce any significant differences in stiffness, the use of CHAPS resulted in a ∼ 35% reduction compared with SDS, the influence of the detergent being more important in the tunica intima. In conclusion, lung matrix stiffness is considerably inhomogeneous, and conventional decellularization procedures do not result in substantially different local stiffness in the acellular lung.
肺生物工程是一种获得潜在可用于移植器官的新方法，它基于使供体肺脱细胞并将干细胞接种到天然支架上。已经使用了各种物理化学方法来使肺脱细胞，并根据有效的脱细胞和基质保存来评估其性能。然而，关于不同脱细胞程序对无细胞肺的局部刚度的影响，尚无数据。然而，这一信息非常重要，因为干细胞在重新接种时直接感知它们将要植入的局部部位的刚性，并且已经表明，基质刚度可以将细胞命运调节为不同的表型。本研究的目的是评估脱细胞程序对五个不同部位（肺泡间隔、肺泡连接、胸膜和血管的内膜和外膜）的无细胞肺局部不均匀刚度的影响。通过在脱细胞肺循环系统中使用/不使用四种不同的方案（有/无）和两种不同的去污剂（十二烷基硫酸钠[SDS]和 3-[(3-胆酰胺丙基)二甲基氨] -1-丙磺酸钠[CHAPS]）对 36 只健康大鼠（Sprague-Dawley，雄性，250-300 g）的肺进行脱细胞处理后，通过原子力显微镜计算杨氏模量来测量局部基质刚度。无细胞肺基质的局部刚度取决于基质内的部位（p<0.001），范围从肺泡间隔处的约 15 kPa 到内膜处的约 60 kPa。无细胞肺的刚度（p=0.003）与脱细胞过程有显著但适度的依赖性。虽然灌注不会导致刚度有任何显著差异，但与 SDS 相比，CHAPS 的使用会导致刚度降低约 35%，而去污剂的影响在内膜中更为重要。总之，肺基质的刚度相当不均匀，传统的脱细胞程序不会导致无细胞肺的局部刚度有显著差异。
