Long-term study on off-the-shelf tracheal graft: A conceptual approach for urgent implantation

Abstract

A wide range of interest has been recently focused on the reconstruction of long-segment tracheal defects, especially in the field of thoracic reconstructive surgery. Although a number of treatment methods for tracheal reconstruction have been developed, reconstruction of critical sized defects (>6 cm) is always a major challenge in trachea surgery. In the field of tissue engineering, reconstruction of tissues using artificial substitutes has shown promises in addressing this challenge, particularly with much success in tracheal reconstruction achieved by multiple institutions. The aim of this study is to develop an off-the-shelf treatment method that can be achieved without imposing cells even for urgent applications to tracheal disorders or injuries. We designed an off-the-shelf tracheal graft without imposing the cells for the concept of urgent transplantation from a porous PCL bellows framework that we developed in our previous works. We then evaluated the application of our off-the-shelf treatment method using an artificial graft in vivo at a proof-of-concept level using a rabbit model. We successfully demonstrated the potential of an off-the-shelf tracheal graft with luminal collagen stratification for immediate application in emergencies that require an artificial graft. Keywords: Tracheal reconstruction, Tissue engineering, Three-dimensional (3D) bioprinting