Tissue-engineered trachea from a 3D-printed scaffold enhances whole-segment tracheal repair in a goat model

Traditional treatment therapies for tracheal stenosis often cause severe post-operative complications. To solve the current difficulties, novel and more suitable long-term treatments are needed. A whole-segment tissue-engineered trachea (TET) representing the native goat trachea was 3D printed using a poly(caprolactone) (PCL) scaffold engineered with autologous auricular cartilage cells. The TET underwent mechanical analysis followed by in vivo implantations in order to evaluate the clinical feasibility and potential. The 3D-printed scaffolds were successfully cellularized, as observed by scanning electron microscopy. Mechanical force compression studies revealed that both PCL scaffolds and TETs have a more robust compressive strength than does the native trachea. In vivo implantation of TETs in the experimental group resulted in significantly higher mean post-operative survival times, 65.00 +/- 24.01 days (n = 5), when compared with the control group, which received autologous trachea grafts, 17.60 +/- 3.51 days (n = 5). Although tracheal narrowing was confirmed by bronchoscopy and computed tomography examination in the experimental group, tissue necrosis was only observed in the control group. Furthermore, an encouraging epithelial-like tissue formation was observed in the TETs after transplantation. This large animal study provides potential preclinical evidence around the employment of an orthotopic transplantation of a whole 3D-printed TET.