Tracheal Tissue Engineering

[摘要] Large airway defects pose a substantial problem to surgeons in both pediatric and adultpopulations. For example, primary tracheal cancers can result in neoplastic lesions, whichare often not diagnosed until the tumor has become inoperable. These patients are palliated,but have a poor prognosis, with only 5% survival after 5 years. Tissue engineered transplantsover a life saving new therapeutic option. Recent reports have demonstrated good midtermresults with decellularized human homograft tissue. However, these experiments have beenlimited to compassionate use. To achieve effcacy necessary for more widespread use furtherstudy is necessary to investigate alternate approaches and optimize the decellularizationtechnique. Additionally, clinical application of this technology will require translation to adecellularized xenograft to obviate human tissue supply limitations. To this end, we comparethe use of 3 alternate detergents (SDS, Triton X-100, and CHAPS) to sodium deoxycholatein the commonly accepted detergent enzymatic method (DEM). Fresh donor rat tracheaswere decellularized using a modified 9-day DEM protocol. The pre-implant scaffolds werethoroughly characterized for each experimental group and implanted for 12 weeks using anorthotopic rat tracheal reconstruction model. It was found that detergent choice stronglyaffects the host remodeling response including host cell infiltration and epithelial differentiation.The clinically relevant sodium deoxycholate and Triton X-100 groups were retestedwith a final peracetic acid (PAA) rinse. It was determined that the use of PAA greatlyimproved the in vivo response of the previously poor performing sodium deoxycholate andmade little improvement to the Triton X-100 scaffold. The optimum configuration, TritonX-100 with a PAA rinse, was selected for translation to a clinically relevant porcine model. Porcine tracheal decellularization was achieved using a modified 14 day DEM protocol with a novel cyclical pressure approach. The suitability of these porcine tracheas for pre-clinicallarge animal testing was verified through mechanical analysis (pressure-diameter and sutureretention) and in vitro seeding experiments with human bronchial epithelial cells.

[发布机构] the University of Pittsburgh