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bioRxiv · 10.1101/587691

In vivo feasibility study of the use of porous polyhedral oligomeric silsesquioxane implants in partial laryngeal reconstruction.

Abstract

BackgroundLoss of substantial volumes of laryngeal tissue after trauma or cancer significantly impairs quality of life. We hypothesised that repair of laryngeal defects with a candidate biomaterial, seeded with mesenchymal stem cells (MSC) and epithelial cells, may offer a therapeutic approach to this unmet need.\n\nMethodMoulded porous polyhedral oligomeric silsesquioxane polycarbonate-urea (POSS-PCU) scaffolds were seeded with human-derived MSC and epithelial cells, were implanted orthotopically into a defect created in the thyroid cartilage in eight pigs and monitored in vivo for 2 months. In vivo assessments were performed at 1, 2, 4 and 8 weeks post implantation. Histology was performed following termination.\n\nResultsImplant operations were uncomplicated. One pig was terminated early (2 weeks post-implantation) following expectoration of its implant. No other mortality or morbidity was observed. Endoscopy showed partial extrusion of implants at two weeks and complete extrusion of all implants by termination.\n\nConclusionsPOSS-PCU moulded laryngeal implants, in the present formulation, are extruded from the site of implantation between two- and eight-weeks post-surgery in pigs. In its present formulation and with the present, one-stage, protocol, this material does not appear to provide a suitable scaffold and vehicle for cells intended for partial laryngeal replacement in pigs.

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Birchall, M. A., Hermann, P., Sibbons, P.. 2019-03-25. In vivo feasibility study of the use of porous polyhedral oligomeric silsesquioxane implants in partial laryngeal reconstruction.. https://doi.org/10.1101/587691

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