Tracheal Regeneration, Retinoic Acid, Collagen, Epithelium, Mucociliary
We acknowledge the funding received for this research under the Programme for Research in Third Level Institutions Cycle 5 & cofunded through the European Regional Development Fund (ERDF), part of the European Union Structural Funds Programme 2007−2013, and the support of the European Molecular Biology Organisation (EMBO) short-term fellowship (ASTF 567-2014). S.A.C. is a Science Foundation Ireland (SFI) investigator (13/1A/1840). CURAM is funded by SFI and the European Regional Development Fund (Grant Number 13/RC/2073). F.O.B.’s laboratory receives funding from SFI (12/RC/2278) and the European Research Council (grant agreement no. 239685) under the EU Seventh Framework Programme (FP7/2007−2013). Collagen was kindly provided by Integra Life Sciences Corporation.
: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-trans 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.
O'Leary C, O'Brien FJ, Cryan SA. Retinoic Acid-Loaded Collagen-Hyaluronate Scaffolds: A Bioactive Material for Respiratory Tissue Regeneration. ACS Biomaterials Science & Engineering. 2017 [in press]
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 4.0 License.