Using separate syringes for each solution, both solutions were simultaneously electrospun (ie, co-electrospun) onto a rotating grounded mandrel (30 revolutions per minute) positioned 20 cm from the syringe tips, with +25 kV charge applied. 10 In summary, 10 wt% polyglycolic acid (PGA) and 5 wt% polylactide-co-caprolactone (PLCL) were separately dissolved in 1,1,1,3,3,3-hexafluoroisopropanol and stirred with a magnetic stir bar for a minimum of 3 hours at room temperature. Grafts were produced as previously described. Specimens were stored in cold phosphate buffered saline (PBS) for approximately 10 minutes until implantation.Ĭo-electrospun nanofiber resorbable tracheal scaffold: Polylactide-co-caprolactone/polyglycolic acid. Transection of the trachea was then performed below the third tracheal ring, and a 5 mm specimen was resected. A 22 G needle was inked using a surgical marker to mark the anterior midline portion along the tracheal segment and the graft to assist with maintaining the orientation during the implant surgery ( Figure 1B). Once the thyroid cartilage, cricoid cartilage, and proximal trachea were identified, circumferential dissection of the trachea was performed at the level of the third tracheal ring in a supraperichondrial plane ( Figure 1B).
#Protein scaffold trachea skin#
Once euthanasia was confirmed and the surgical site was prepared, a vertical midline incision was made through the anterior neck skin from the clavicles to the hyoid bone with retraction of the strap muscles using a dissection microscope ( Figure 1A). Six- to 8-week-old specific pathogen-free C57BL/6 female mice were euthanized using an overdose cocktail of ketoprofen (10 mg/kg), xylazine (20 mg/kg), and ketamine (200 mg/kg, intraperitoneal) and bilateral pneumothoraces. 7– 9 In this report, we developed a mouse model of orthotopic tracheal replacement using electrospun scaffolds using both nonresorbable and resorbable polymers, comparing the biomechanical properties of the 2 scaffolds, histologic findings, and overall survival. 4– 6 Using electrospinning, small tubular scaffolds can be fabricated to mimic native extracellular matrix on a nanoarchitectural level. The use of a synthetic scaffold to support tracheal regeneration would avoid the need for donor tissue, spare a lengthy decellularization process, permit off-the-shelf applications and is easily customizable. 2 While the feasibility of decellularized tracheal constructs have been reported, orthotopic implantation of biosynthetic tracheal scaffolds in a mouse model has yet to be explored. The development of a mouse model that recapitulates the complications seen in humans would allow for the application of transgenic models that would both define mechanisms and subsequent modification of these mechanisms to attenuate graft stenosis and accelerate regeneration. Critical to the development of a tissue-engineered trachea is the delineation of the cellular and molecular mechanisms driving regeneration as well as the complications that prohibit translation from the bench to bedside. 1 Animal models including sheep, dogs, pigs, rabbits, and rats have been used to study the in vivo performance of tissue-engineered tracheal constructs. The clinical translation of tissue engineered tracheal grafts has been limited due to graft collapse, stenosis, and delayed epithelialization.