Latner Thoracic Surgery Research Laboratories, Division of Thoracic Surgery, University Health Network and McEwen Centre for Regenerative Medicine, Toronto, Ontario, Canada.
Tissue Eng Part C Methods. 2012 Aug;18(8):614-23. doi: 10.1089/ten.TEC.2011.0579. Epub 2012 Apr 18.
Tracheal reconstruction is indicated in cases of malignancy, traumatic injury, and subglottic or tracheal stenosis. Recent progress in airway transplantation has provided renewed optimism for potential solutions for defects involving more than half of the tracheal length in adults or one-third of the tracheal length in children. Biologic scaffolds derived from decellularized tissues and organs have shown great promise in tracheal allotransplantation, and cyclical decellularization techniques have been hypothesized as abrogating the need for immunosuppressive therapy. In this study, we performed a direct comparison of three decellularization protocols (Protocols A, B, and C) previously described in the literature, two of which were described in tracheal tissue (Protocols A and B). We concentrated on the immunogenicity within the epithelium and mucosa, quantified and qualified the extracellular matrix (ECM) components, and performed compliance measurements on large circumferential decellularized tracheal scaffolds following cyclical decellularization techniques using all three protocols. Quantitative measurements of glycosaminoglycans (GAGs) showed a significant decrease in the mucosal component following 17 cycles of all 3 protocols as well as a significant decrease of GAGs in the cartilaginous component following cycles 1, 9, and 17 of Protocol A and cycle 17 of Protocol C. Compliance measurements were also shown to be different between the protocols, with grafts becoming more compliant at physiologic pressures after cyclical decellularization with Protocols A and B and slightly less compliant but remaining similar to native trachea using Protocol C. Positive staining for anti-major histocompatibility complex Class I (anti-MHCI) and anti-MHCII remained within the submucosal glandular components despite multiple cycles of decellularization using all three protocols. This study illustrated that there are significant differences in ECM composition and resultant structural integrity of decellularized tracheal scaffolds depending on the decellularization protocol. Protocol B was shown to maintain the GAGs components despite an increase in tracheal compliance, while Protocol C decreases GAGs components following multiple cycles, despite showing a tracheal compliance resembling that of the native trachea at physiologic airway pressures.
气管重建适用于恶性肿瘤、创伤和下呼吸道或气管狭窄的情况。气道移植的最新进展为成人超过一半的气管长度或儿童三分之一的气管长度的缺陷提供了潜在解决方案的新希望。脱细胞组织和器官衍生的生物支架在气管同种异体移植中显示出巨大的潜力，并且循环脱细胞技术已被假设为消除对免疫抑制治疗的需求。在这项研究中，我们对之前文献中描述的三种脱细胞方案（方案 A、B 和 C）进行了直接比较，其中两种是在气管组织中描述的（方案 A 和 B）。我们专注于上皮和粘膜内的免疫原性，量化和定性细胞外基质（ECM）成分，并使用所有三种方案进行循环脱细胞技术后对大圆周脱细胞气管支架进行顺应性测量。糖胺聚糖（GAGs）的定量测量表明，所有 3 种方案的 17 个循环后粘膜成分显著减少，以及方案 A 和 C 的第 1、9 和 17 个循环和方案 C 的第 17 个循环中软骨成分中的 GAGs 显著减少。顺应性测量也表明方案之间存在差异，在使用方案 A 和 B 进行循环脱细胞后，移植物在生理压力下变得更具顺应性，而使用方案 C 时，移植物的顺应性略低，但仍与天然气管相似。尽管使用所有三种方案进行了多次脱细胞处理，但抗主要组织相容性复合物 I 类（抗-MHCI）和抗 MHCII 的阳性染色仍存在于粘膜下腺成分中。这项研究表明，根据脱细胞方案的不同，脱细胞气管支架的 ECM 组成和由此产生的结构完整性存在显著差异。尽管气管顺应性增加，但方案 B 显示出保持 GAGs 成分的能力，而方案 C 在多次循环后减少 GAGs 成分，尽管在生理气道压力下显示出类似于天然气管的气管顺应性。
