O'Leary Cian, O'Brien Fergal J, Cryan Sally-Ann
School of Pharmacy, Royal College of Surgeons in Ireland, 123 St. Stephen's Green, Dublin 2, Ireland.
Tissue Engineering Research Group, Department of Anatomy, Royal College of Surgeons in Ireland, 123 St. Stephen's Green, Dublin 2, Ireland.
ACS Biomater Sci Eng. 2017 Jul 10;3(7):1381-1393. doi: 10.1021/acsbiomaterials.6b00561. Epub 2017 Feb 22.
Clinical interventions for extensive tissue injury to the larger airways remain limited. Recently, respiratory tissue engineering strategies have emerged with a variety of biomimetic materials and tissue constructs to address these limitations, though rapid epithelialization of the construct with mucociliary function is still largely unresolved. The overall objective of this study was to manufacture an all- retinoic acid (atRA)-loaded bilayered collagen-hyaluronate (atRA-B) scaffold as a platform technology for tracheal tissue regeneration. atRA-loaded scaffolds were fabricated using a customized lyophilization process and characterized for drug loading and release properties using HPLC, followed by validation of their bioactivity using human primary tracheobronchial epithelial cells. atRA-loaded materials were reproducibly manufactured and exhibited the release of atRA following their hydration over 8-28 h that was significantly affected by collagen cross-linking. An optimal formulation consisting of 10 μg/mL atRA in a collagen-hyaluronate suspension to manufacture the scaffold film layer was identified and used to develop the atRA-B scaffold. Immunofluorescence studies and RT-PCR revealed that the atRA-loaded biomaterials increased the expression of two epithelial markers of mucociliary differentiation, MUC5AC and β-tubulin IV, via upregulation of MUC5AC and FOXJ1 genes, both in epithelial monoculture and in a 3D scaffold coculture system with lung fibroblasts. Overall, this study has demonstrated that the atRA-B scaffold can enhance functional epithelialization in primary tracheobronchial cells and can potentially pioneer the development of a novel and biocompatible device to address a currently unmet clinical need in tracheal replacement.
针对大气道广泛组织损伤的临床干预措施仍然有限。最近，呼吸组织工程策略已经出现，采用了各种仿生材料和组织构建体来解决这些局限性，尽管构建体具有黏液纤毛功能的快速上皮化在很大程度上仍未得到解决。本研究的总体目标是制造一种负载全反式维甲酸（atRA）的双层胶原-透明质酸（atRA-B）支架，作为气管组织再生的平台技术。使用定制的冻干工艺制备负载atRA的支架，并使用高效液相色谱法对其药物负载和释放特性进行表征，随后使用人原发性气管支气管上皮细胞验证其生物活性。负载atRA的材料能够可重复制造，并且在水合后8-28小时内表现出atRA的释放，这受到胶原交联的显著影响。确定了一种最佳配方，即在胶原-透明质酸悬浮液中加入10μg/mL atRA来制造支架薄膜层，并用于开发atRA-B支架。免疫荧光研究和逆转录-聚合酶链反应显示，负载atRA的生物材料通过上调MUC5AC和FOXJ1基因，在单层上皮培养以及与肺成纤维细胞的三维支架共培养系统中，增加了黏液纤毛分化的两种上皮标志物MUC5AC和β-微管蛋白IV的表达。总体而言，本研究表明，atRA-B支架可以增强原发性气管支气管细胞中的功能性上皮化，并有可能开创一种新型生物相容性装置的开发，以满足目前气管置换中未满足的临床需求。
