|Title:||A composite tissue-engineered biomaterial scaffold with refined mechanical properties and vascularisation for tracheal regeneration|
|Author(s):||T Khalid M Lemoine SA Cryan FJ O’Brien C O’Leary|
|Institution:||Royal College of Surgeons in Ireland|
|Poster:||Click to view poster|
|Abstract:||Attempted tracheal replacement efforts thus far have had very little success. Major limiting factors have been the inability to efficiently re-vascularise and mimic the mechanical properties of native tissue . The major objective of this study was to optimise a previously developed collagen-hyaluronic acid scaffold (CHyA-B), which has shown to facilitate the growth of respiratory cells in distinct regions , as a potential tracheal replacement device.|
A biodegradable thermoplastic polymer was 3D-printed into different designs and underwent multi-modal mechanical assessment. The 3D-printed constructs were incorporated into the CHyA-B scaffolds and subjected to in vitro  and in vivo  vascularisation.
The polymeric backbone provided sufficient strength to the CHyA-B scaffold, with a yield load of 1.31-5.17 N/mm and a flexural moduli of 0.13-0.29 MPa. Angiogenic growth factor release (VEGF and bFGF) and angiogenic gene upregulation (KDR, TEK-2 and ANG-1) was detected in composite scaffolds and remained sustainable up to 14 days. Confocal microscopy and histological sectioning confirmed the presence of infiltrating blood vessel throughout composite scaffolds both in vitro and in vivo.
By addressing both the mechanical and physiological requirements of tracheal scaffolds, this work has begun to pave the way for a new therapeutic option for large tracheal defects.
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