Experimental bioprosthetic reconstruction of the trachea

Abstract

We removed the tracheas from sacrificed laboratory animals and subjected this tissue to multi-step chemical processing. This method allowed us to preserve the cartilage and reduce its antigenicity, thus creating a bioprosthesis very similar to the host tissue. By using allogeneic and xenogeneic prostheses so prepared, no signs of immune rejections were seen following heterotopic or orthotopic implantations. The transplanted cartilage remained stable for periods ranging up to 21 weeks in recipient rats, while partial morphologic integrity of the cartilage was seen up to 1 year in pigs. Reepithelialization of the transplant with ciliated epithelium was completed in all specimens 12-24 weeks following surgery. Segmental replacement of up to one third of the whole trachea was possible in rats, whereas similar segmental replacements failed in pigs. We also found that successful reconstruction of window-shaped defects was possible. We consider our tracheal bioprosthesis to be superior to cialit-preserved grafts and also to most other biological reconstruction procedures.

Tracheal Tissue Engineering

“…implanted as allografts and autografts. As expected, rejection was not observed, but gross morphological survival of cartilage was only observed in rats [53]. Sterilized and lyophilized aortic allografts over polyethylene tubes were implanted in dogs, while the stents prevented stenosis, longitudinal contraction damaged the proximal and distal ends of the trachea [54].…”

Prosthetic reconstruction of the trachea: A historical perspective

“…This has focussed on homografts, various composite strategies (including further work on porous prostheses) and latterly, tissue engineering[1,5,9,10,12,14,40-67]. …”

“…Scherer et al[67] were first to experiment with bioprostheses by transplanting tracheas from various animals as autografts, allografts and xenografts. Rejection seemed to be avoided[31,67].…”

Tracheal Replacements: Part 2

“…29 The porous nature allows ingrowth of connective tissue, which initiates the migration of tracheal epithelium and further incorporates the mesh prothesis into the remaining tracheal tissue. The minimal porosity necessary for capillary ingrowth is 40 to 60 m. 30 Regenerative tracheal epithelium evolves from squamous to cuboidal to pseudostratified and then finally ciliated cells. 31,32 Inadequate structural support has been the predominant problem with experimental mesh prostheses.…”